* Hide vertically hidden ranged items in groups that are not visible
* Add element to templates options
* Fix comment typo
* Add documentation for react mounting
* add react example
* Fix typo
* fix title
* Fix review comments
* Add vis-drag-center to fix dragging bug when template is react component

* 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

Timeline will check for the property 'editable' on individual items.

  if editable === true
    ignore timeline option 'editable'
    allow item to be edited
  else if editable === false
    ignore timeline option 'editable'
    do not allow item to be edited
  else
    use timeline option 'editable'

If two items are selected and one is not editable, only the editable
item is draggable.

This change required the css class .vis-editable be moved from the
item set to the individual item containers to maintain proper styling.

This is primarily designed for the graph2d line graph.