Fixed issue #67: daterange cannot hande a min or max value of 0 (1-1-1970 00:00)
Added support for custom stack order function
Fixed bug when dragging timeline items across group rows
Merge pull request #76 from bharling/master

Timeline Items lose custom css classes when moved up or down timeline rows
stackMoveToFinal iterates over finalItems, not currentItems

This makes it possible, to filter items, while building up the
finalItems array. (most other loops are already constructed alike)
Timeline-constructor allows inheritation

When no container is supplied, the timeline constructor simply exits, so
that no runtime error is triggered, and inheritation by
"MyClass.prototype = new links.Timeline(null);" is possible.
Fixed bug in stackMoveOneStep loop

It was iterating over currentItems, but using the index for lookup in
the finalItems-Array
Merge pull request #71 from mrmoosehead/StackingOrderFunction

Added support for custom stack order function
Merge pull request #78 from gagabla/master

Allow extension of links.Timeline using inheritation
Clusters are now updated on changed data. Fixed option dragAreaWidth. Fix in dragging an item to an other group
Newly created items are now rendered after the 'add' trigger instead of before (Fixed #75)
Fixed 'ready' event being fired before an event listeners can be attached (Fixed #69).
Fixed issues with dates on millisecond scale and negative years (Fixed #54, Fixed #19, and possibly #81)
Fixed a rendering error on IE8-
Released Timeline version 2.4.0