This addresses #1982 and #1417.

It possibly reduces performance, but correctness seems better.

* Fix redraw order
* Fix error when option is not defined
* Allow template labels
* Add .travis.yml file
* Add experiment travis code
* Fix react example
* Fix mousewheel while dragging item bug
* Return removed lines

* Fix redraw order
* Fix error when option is not defined
* Allow template labels
* Add .travis.yml file
* Add experiment travis code
* Fix right click button bug when dragging item

- Also updated docs and examples for this
 - Fixed the positioning of the tooltip if groups was enabled
 - Removed missing parameters from Popup docstring

* Fix redraw order
* Fix error when option is not defined
* Allow template labels
* Fix boolean types bug
* Add subgroup stacking
* Almost finish subgroup stacking
* Play with examples for subgroup order
* Fix stacked subgroups
* Fix subgroup stacking
* Add stackSubgroups option
* Fix example
* Add docs
* Fix onRemove item subgroups recalculate
* Return subgroup example and add stackSubgroup example
* Split stackSubgroup example to subgroup/html and expectedVsActualTimesItems.html

* Added HTML tooltip support for Timeline

* Fixed tooltip position on Firefox

* Added Timeline tooltip example

* Updated tooltip location to be next to the mouse

* Added HTML element to example

* Fix groupEditable
* Fix group drag in vertical direction bug
* Fix indentation
* Add initial nestedGroups property
* Fix redraw order
* Get nested groups hiding working
* Add order to nestedGroups
* Fix up example
* Add support for intially closed nested groups
* Add nested groups indentation
* Fix indents
* Add nested groups docs
* Fix example
* Revert indents
* Add classes to nested and nesting group labels and add nesting group css
* Use pure css for nested group icons
* Remove commented off lines and unnecessary btn
* Fix indents
* Add support to showNested:false in group
* Add semicolon
* Remove empty lines

* Fix redraw order

* Fix initial drag item bug

* Fix indents

* Fix redraw order

* Add initial itemVisibleFrame

* Add visibleFrameTemplate option

* Improve example

* Rename and fix example

* Fix comments from PR

* Fix example

* Fix redraw order
* Fix calling dragStart mote than once

* Fix redraw order
* Fix IE10 support for dnd

* Fix redraw order
* Add elements censor and event to emitter
* Fix all recursive loop in json event
* Add docs for event emitted

* Add support to fixed times drag and drop
* Fix IE support for drag and drop
* Add support to IE pointer location and data setting/getting

* Fix groupEditable
* Fix group drag in vertical direction bug
* Fix indentation

* 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

* 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!

* 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 initial scroller without options
* Add initial scroll without an option
* Add verticalScroll option
* Fix scrollbar positions
* Add docs
* fix example
* remove jquery dependency
* Fix example
* Fix review comments

Add flag to check whether an item in the Itemset is currently being dragged

added docs