* Added group option to change the visibility of a group
* updated the groupsEditable example page to demo the use of this feature
* updated the timeline documentation to describe this option
* Fixed bug introduced in #2284 where overrideItems is set to true when boolean is provided
* Added the option of supplying object to item.editable with updateTime, updateGroup, and remove functioning similarly to timeline.editable but only on a single item
* Updated Documentation to reflect the new feature
* Updated the individualEditableItems example page to show feature usage.
* 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.
* 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
* Added class Range for Min/Max value pairs.
* Processed review feedback, added comments.
* Fixed jsdoc tags; reviewed commenting
* Final fixes to commenting