* - Added support for vertical scrolling while the timeline is focusing on an element, both for animated and non-animated calls of focus

* - Adjusted item offset calculations to use the item parent
- Turned on animation for the focus in the example
- Updated function documentation

* - Fixing lint issues

* - Added documentation for the new 'frameCallback' parameter of 'setRange'
- Fixed the documentation on 'setRange' for the 'callback' parameter
- Fixed code not meeting style guidelines

* - Updated the example for "setSelection" to be more clear about what the example buttons do. Focus the language to be more consistent with that fact that the demo uses "setSelection"

* - Added support for stacking items within individual subgroups while subgroupStack is on

* - Adjusted location of visibility check to cover subgroup stacking

* - Fixing linting issues

* - Updated subgroup stacking to optionally take a 'subgroupStack' parameter of "true", which enables stacking in all subgroups
- Fixed code to meet style guidelines
- Updated documentation

* Make items redraws return queues

* Parallel initial items redraw

* Seperate read and write actions in items

* Parallel all items redraws

* Remove comments

* Fix linting comments

* Fix redraws on actions

* Add stress example

* Fix example files

* Explain and fix example

* Fix comment issues

* Small refactoring in Label._drawBackground()

* Added size calculation to Label, basic framework for detecting click on label.

* First fully working version of label click.

* Put in extra checks, refactored visibility of labels for more general usage.

* Final fixes to code; added to example and in docs

* Adressed review comments

* Add next attempt to fix Travis unit test bug

* Addressed review issues

Fixes #3483.

If `shape: 'image'` is defined as option, this was used for initializing hidden cluster nodes during layout initialization.
However, because no image is being passed, this led to an exception.

This fix prevens shape `image` from being used for hidden cluster nodes. In addition, some extra fields for these nodes are
now overridden for some performance improvament.

* The next fix on Travis unit test failure

This is the next escalation on the war against the Travis unit tests failing (which came into being by yours truly).
By accident, I could recreate the unit test failure on my development machine. This led to a more directed effort to
squash the bug.

The insight here is that test `(window === undefined)` fails, but `(typeof window === 'undefined`)` succeeds. This undoubtedly has to do with the special status `window` has as a global object.

Changes:

- Added check on presence of `window` in `Canvas._requestNextFrame()`, fixed local source errors.
- Added catch clause in `CanvasRendered._determinePixelRatio()`
- small fix: raised timeout for the network `worldCup2014` unit test

* Preliminary refactoring in utils.js

* Added unit tests for extend routines, commenting and small fixes

* More unit tests for extend routines

* - Completed unit tests for extend routines in
- Small fixes and cleanup in `util.js`
- Removed `util.protoExtend()`, not used anywhere

* Added unit tests for known font options

* Interim save before trying out another proto chain strategy

* Fixed problem in first example #3408

* Removed silly file that shouldn't be there

* Added unit test for multi-fonts

* Comment edits

* Verufy unit tests, small adjustments for groups

* Further work on getting unit tests to work. PARTS NEED TO BE CLEANED UP!

* Further tweaks to get unit tests working

* All unit tests passing

* Fixes due to linting

* Small edits

* Removed prototype handling from font pile

* Fixes during testing examples of #3408

* Added unit test for edge labels, small fixes

* Added unit tests for shorthand string fonts; some tests still failing

* All unit tests pass

* Removed Label.parseOptions()

* Completed shorthand font tests, code cleanup, fixed choosify for edges

* Addressed review comments

* Addressed review comments, cleanup

* Label performance improvements

* Label cleanup

* Fix drag performance in IE

* Fixed broken images still trying to draw

* Fixed merge and lint issues

* IE11 svg image fixes

* Fixed broken images still trying to draw

* Fixed lint error

* Refactoring of label splitting; new unit test still failing.

* Label acc size calculations to separate methods.

* Final fixes and cleanup

* Added unit test for Array.prototype mangling - first passing version

* Enhanced unit test for prototype stressing to catch more illegal for-in loops

* Fixed all for-in linting violations

* Implement group redraw @grimalschi performance enhancement

* Fix JSDoc for redraw

* Remove commented out in itemset

* Remove fasdom

* Clean up queue functions in group redraw

* Fix mistake in comments

* Remove extra read-write from _didResize

* Resolve review comments

* Fix ranged item resizing bug

* remove parameter that wasn;t used

* Implement group redraw @grimalschi performance enhancement

* Fix JSDoc for redraw

* Remove commented out in itemset

* Remove fasdom

* Clean up queue functions in group redraw

* Fix mistake in comments

* Remove extra read-write from _didResize

* Resolve review comments

* The next fix on Travis unit test failure

This is the next escalation on the war against the Travis unit tests failing (which came into being by yours truly).
By accident, I could recreate the unit test failure on my development machine. This led to a more directed effort to
squash the bug.

The insight here is that test `(window === undefined)` fails, but `(typeof window === 'undefined`)` succeeds. This undoubtedly has to do with the special status `window` has as a global object.

Changes:

- Added check on presence of `window` in `Canvas._requestNextFrame()`, fixed local source errors.
- Added catch clause in `CanvasRendered._determinePixelRatio()`
- small fix: raised timeout for the network `worldCup2014` unit test

* Preliminary refactoring in utils.js

* Added unit tests for extend routines, commenting and small fixes

* More unit tests for extend routines

* - Completed unit tests for extend routines in
- Small fixes and cleanup in `util.js`
- Removed `util.protoExtend()`, not used anywhere

* Added unit tests for known font options

* Add endpoint 'bar' to Network

Fixes #3412

- Adds class `Bar` and handling to `EndPoints.js`
- Adjusted `options.js` for endpoint, minor code changes
- Added to example `network/edgeTypes/arrowTypes`.
- Added to edges documentation

* Grumbl fix travis unit test yet again. Go die already!

* Network: Fixes sorting on Layout sorting, refactoring.

Fix for #3403

Chromium has divergent behaviour on sorting of `undefined` values, a check has been added for these.

The fix itself is small, it adds a check on `undefined` in the sorting function(s).

In addition:

- Fixed off-by-one error on tree index
- Refactored away checks on visibility by replacing `_isVisible()` with a Strategy pattern for direction

The latter removes a long-standing eyesore in `LayoutManager`; it's probably also faster.

There is some hope that these fixes will improve the hierarchical layout initialization, which has had
problems for quite a while.

* reformat code block

* Add next attempt to fix Travis unit test bug

* Fix unit test - timeout

* Adjustments for comment reviews

* Moved direction strategies to separate module; added fix for 'window is undefined'

This is the next escalation on the war against the Travis unit tests failing (which came into being by yours truly).
By accident, I could recreate the unit test failure on my development machine. This led to a more directed effort to
squash the bug.

The insight here is that test `(window === undefined)` fails, but `(typeof window === 'undefined`)` succeeds. This undoubtedly has to do with the special status `window` has as a global object.

Changes:

- Added check on presence of `window` in `Canvas._requestNextFrame()`, fixed local source errors.
- Added catch clause in `CanvasRendered._determinePixelRatio()`
- small fix: raised timeout for the network `worldCup2014` unit test

* Moved endpoint-specific code to module EndPoints

* Further decomposed functionality for endpoints

* Added commenting, notably for typedef's

* Add next attempt at fixing travis bug

* Fixes issue #3428 - Adds locale for Chinese (cn)

* Corrects spacing in Chinese locale definition.

* Added default sizes for nodes without labels

* Next attempt at fixing travis problem

* Fix on calculation of multifont labels - the height was calculated too large.

* added hexagon shape to the node.

* Updated function for hexagon shape.js

* Modifid the shape login for hexagon

* Remove this.translate from the Shape.js for hexagon

* updated hexagon draw logic

* Fixed code review comments and update the branch

* Updated changes in test.js

* Corrects usage of @static jsdoc annotation

* Correct unresolvable types

* Correct types in jsdoc and remove extraneous @class & @constructor jsdoc

* Remove incorrect @static jsdoc

* Adds missing jsdoc for param copyFromGlobals

* correct jsdoc in util

* Corrects casing on jsdocs

* Swaps @inheritDoc to @ignore for constructors where constructor args are documented in the class

* Instantiates Errors with `new`

* Addresses improperly defined @callback tags.

* Split callbacks out to separate jsdoc

* Moves constructor jsdocs back to constructor and drop @ignore.

* Adds unit tests for add, setOptions and on/off

* removes extraneous return value name in @throws tag of jsdoc

* First fix for opening clusters, added unit tests

* Added opening of child cluster to parent cluster

* Added more tests for multi-level clusters

* Commenting fixes

* Added unit tests for option allowSingleNodeCluster, fixes due to that

* Added test for allowSingleNodeCluster with nested clusters

* Fixes due to linting

* Removed TODO from code

(#3395)

A recurring problem during travis tests is that global variable `window` can get reset while `Network` tests using a mock canvas object are running.
This issue has been adressed several times, but it still happens. This PR reduces the possibility of it happening again to a minimum.

PR's affected by this issue should be merged with this fix and re-submitted. At time of writing, these are:
- #3402
- #3405
- #3399

Chances are it will occur sporadically for other PR's as well.
Labelling this `High Priority` because it indrectly affects unrelated PR's.

Fix for #3367

Changes:

- Clustered nodes with shared connections are added to the same cluster
- joinCondition value `null` handled as `undefined`
- Fixed bug on adding clusters if joinCondition present and returns true

Unit tests have been added to `Network.test.js` for these changes.

* Added commenting for options, refactored choosify()

* Refactored updateLabelModule()

* added comment at node creation

* Completed fix for #3350

* parseOptions() different handling for bridged/extended; unit tests for reversal of options

* Fixes on linting and unit testing

* Enables require MethodDefinition for require-jsdoc lint rule and corrects 66% of missing Method Definitions

* Adds jsdoc for all remaining methods and corrects @class/@constructor documentation

* Define values more accurately

* Correct bugs that prevent jsdoc generation

* Adds missing @extends for constructors

* Adds names to constructors

* Removes redundant .eslintrc from graph3d, lints the rest of the code base, and enables valid-jsdoc lint rule

* Corrects lint violations

* Add support for edge style

* Update for TODO: support of solid/dotted/dashed edges (attr = 'style')
* Edge styles are defined as var edgeStyles in parseAttributeList().

* Add example for edge styles

Add an editable example for playing DOT edge styles

* Correct typo and remove TODO description

* Correct typo of filename from 'dotEdgeSytles.html' to
  'dotEdgeStyles.html'.
* Remove TODO description of the issue for edge style

* Tightens up jsdoc lint rules on timeline

* Adds missing options param

* Enable unit testing for module Network

Adds mocks for certain components, in order to let module `Network` be run in unit tests.

Changes:

- Create a mock object for `hammer.js` when running browserless. The inspiration is taken from [here](https://github.com/uber/deck.gl/pull/658)
- Create a mock function for `window.requestAnimationFrame()` when running browserless in `network/modules/CanvasRenderer.js`
- Added unit test for `Network` to show that unit testing for it now works
- Fixed naming of container in `test/Graph3d.test.js`

Since `hammer.js` is also used in other modules, this fix is potentially an enabler for full-module unit tests for those as well.

* Cleanup unit test Network

* Fix for unit test

* Added example networks to unit test

* Fix error in loading disassemblerExample

* Network unit test final fixes

* Adjusted comments

* Fix sorting of nestedgroups when groups added after initial groups setting

* Fix nesteded groups logic when adding and removing

* Remove empty lines

* Fix comments from PR

* Remove spaces from empty line

* Fix PR review comments

* weekly scale minor label fix

* don't break lint guidelines

* ignore linting

* fixes showMajorLabel issue in #3246

https://github.com/almende/vis/issues/3246

* fix at TimeStep level, for weekly mode, when showMajorLabels == false

* pass options in TimeStep construction

* Tighten up lint rules in graph3d

* remove extra line

* Change lint rules

* Get eslint passing with require-jsdoc

* First working version of updating clustered edge

* Added fix for #1315 as well

* Enable unit testing for module Network

Adds mocks for certain components, in order to let module `Network` be run in unit tests.

Changes:

- Create a mock object for `hammer.js` when running browserless. The inspiration is taken from [here](https://github.com/uber/deck.gl/pull/658)
- Create a mock function for `window.requestAnimationFrame()` when running browserless in `network/modules/CanvasRenderer.js`
- Added unit test for `Network` to show that unit testing for it now works
- Fixed naming of container in `test/Graph3d.test.js`

Since `hammer.js` is also used in other modules, this fix is potentially an enabler for full-module unit tests for those as well.

* Cleanup unit test Network

* Added unit test for fix issue #1218

* Adding test for #1315 - Interim save

* Completed unit test and fixes for #1315

* Added fixes for #1291

* Added unit test for #1219

* Added header comment for Clustering.js, small fixes

* Fix for unit test

* Added example networks to unit test

* Fix error in loading disassemblerExample

* Network unit test final fixes

* Fixes for linting

* Fixed essential typo

* Fixed linting error

* Fixed unit test

* Fixed unit test again

* Disable the default handling of the pinch event when handling it.

* Also disable the touch events to prevent double tap zooming.

This PR contains two small fixes to ensure that all examples rung.
I noticed that some examples weren't working, so I tested them all.