Moved recurring code for StepNumber to start() method

Added method for drawing lines between 3D points

* Removed restriction to allow clusters of a single node; Default functionality remains the same;  Also added new example
* Add documentation for allowSingleNodeCluster, and removed excessive cluster() calls in example.
* Changed documentation as per request.

Translation of all data points to single method.

Fixed getPoint for same node edges

Added 2D line drawing method

* Hide vertically hidden ranged items in groups that are not visible
* Fix misspelling
* Fix examples that do not contain groups
* Add example for vertical hidden ranged items
* Fix indent format in RangeItem
* Fix example
* Fix other examples after addition of vertical hiding range items in groups
* Add case of zero margin axis
* Fix commented out lines in examples
* Fix vertical visibility bug

Network: edge-endpoint 'circle'

* Hide vertically hidden ranged items in groups that are not visible
* Add element to templates options
* Fix comment typo
* Add documentation for react mounting

Networks are exported as a JSON array containing an array of objects representing each node in the network. Each node contains an Id, it's x and y coordinates and the nodes it is connected to.

Import converts the JSON to a vis DataSet and then regenerates the network using each node's attributes, inserting it in the same coordinates and with the same number of connections as before.

fixes #2073

* Hide vertically hidden ranged items in groups that are not visible
* Add custom function format for time labels
* fix misspell
* remove spaces
* remove backspace
* add backspaces
* Add docs and examples
* Fix docs

make bundleing with webpack possible

* Add the source data to Point3d objects in Graph3D; This allows more complex tooltips, using information sent from the server + the source object
* Update PR as requested
* Convert tabs to spaces; Vim config was off, edited in sublime instead

Use requestAnimationFrame to throttle redraws

* Hide vertically hidden ranged items in groups that are not visible
* Add rtl to timeline options docs
* Fix misspelling
* Update RangeItem.js

* fixes #2092

* fixes #2064

* generate individual css files; fixes #1969
* simplified css bundleing
* add new generated dist-css files
* use chart specific css files in the examples

* Hide vertically hidden ranged items in groups that are not visible
* Fix misspelling
* Fix examples that do not contain groups
* Add example for vertical hidden ranged items
* Fix indent format in RangeItem
* Fix example
* Fix other examples after addition of vertical hiding range items in groups
* Add case of zero margin axis

* removed everything build related
* added keywords because it is recommended

* replaced deprecated gulp-minify-css with gulp-clean-css
* updated mocha

* Added getBaseEdge, getClusteredEdges updateEdge and updateClusteredNode to allow option changes of the clustered edges as they are no longer the original base Edge

changing edge color is a good example.
i.e network.clustering.updateEdge(originalEdge.id, {color : '#aa0000'});
will now update all edges including the ones that were created when clustering.

Also when clicking on a clustered edge the event returns the clustered Edge id, which doesn't mean a lot.
This can be now converted back into the original edge with
network.clustering.getBaseEdge(clusteredEdge.id)

Similar with updateClusteredNode
This new method allows the options to be changed on a clustered Node.

i.e clicking on a clustered node gives its clustered node id.
Want to change the clustered image to a star then do this
 network.clustering.updateClusteredNode(clusteredNodeId, {shape : 'star'});

* Updated docs with getClusteredEdge, getBaseEdge, updateEdge and updateClusteredNode

Also added method subsections into contents

* Added better error handling to updateEdge and updateClusteredNodes

corrected errors spotted by @mojoaxel

* Added example html demonstrating getBaseEdge, getClusteredEdges updateEdge and updateClusteredNode