Timeline: updated group.content description to show that it can be an element

Update index.html of Graph3D

dataColor.fill and dataFill.stroke had wrong descriptions.

* Timeline:
* Add overrideItems sub-property to timeline.editable
* Change behavior to override item.editable when overrideItems=true
* Added new example for timeline/editing to higlight differeing editable behaviors.
* Update timeline doc to reflect addition of timeline.editable.overrideItems
* Timeline - fixed logic oversights found in editable override testing
* Timeline - enable changeGroup when item.editable = true and not overriden
* Timeline - Small format changes to documentation and example pages for overrideItems

* Important performance enhancement supporting incremental changes to large graphs, these were too slow due to doing a full item conversion on each add().
Note: the data handling side of graph2d is currently somewhat over-engineered (=too complex) It can use some simplification....

* Fixed style based on feedback.

marked development version as SNAPSHOT

v4.17 release

updated how_to_puplish

fixes DataView.refresh bug introduced with #2189

fixed bug introduced by #2248

Revert "Timeline: options.editable to override item.editable"

* Add initial onChange item tooltip
* Add example and tooltipOnItemEdit template option
* Add docs and rename option
* Fix docs
* Fix example
* Change example's item types
* Fix point item tooltip
* Fix comments from PR and support bottom orientation properly
* Add semi-colon

@simo9000 Thanks!

updated example to support the safari browser

generate details source maps of webpack modules

ignore dist folder in development

improved data serialisation of timeline data

* Add initial experiment
* Register drag and drop events
* Add initial drag and drop support
* Add drag and drop support for all types of objects
* Fix example
* Clean up code and add comments
* Fix example
* remove font awesome
* Fix example style
* Add meta tag to example and add selected when dropped

* Add zoomIn and zoomOut to timeline core functionality
* Fix example
* Fix jsdocs params
* inforce zoom percentage to be between 0 and 1

* Added class Range for Min/Max value pairs.
* Processed review feedback, added comments.
* Fixed jsdoc tags; reviewed commenting
* Final fixes to commenting

* Fix PR comment
* Remove extra line

Support parent dir for RTL timeline and fix a small bug for editable point items

* Should fix issue #2100 and fix another issue we discovered around clusterByConnection leaving phantom edges.
* fixed a wrong variable name
* fixed DataView.test.js assert
* Update Canvas.js
* remove whitespace; remove end of file newline on Canvas.js
* strip end of file newlines
* fixed styling. spacing, semicolons, line length

Fix templates and Item options