now using a minimum texture size for filters (closes #312)

to avoid constant texture recreation when filter region gets small.
auto-trimming number of used quad batches (closes #329)
cleaning
now using a stable sort algorithm for 'sortChildren' (closes #304)

It's a merge sort algorithm that doesn't do any allocations while it runs.
fixed mergeSort result order
fixed draw count display

It was wrong when there were only quads on the stage (no images).
added 'alignPivot' method to DisplayObject class (closes #293)
added optional 'id' paramter to 'TouchEvent.getTouch' method (closes #198)
Merge remote-tracking branch 'refs/remotes/upstream/master' into fastMathNoApparat

Conflicts:
	starling/src/starling/display/DisplayObject.as
	starling/src/starling/display/DisplayObjectContainer.as
now removing text field from Button if text is empty
now logging warning when adding the same asset name twice (closes #339)

Previously, an exception was thrown.
added support for RectangleTextures in AIR 3.8
Adding numerical id public variable numId to DisplayObject
Optimization of removeChildAt if there is no dispatcher
Merge remote-tracking branch 'refs/remotes/upstream/master' into fastMathNoApparat
now broadcasting keyboard events to all display objects
added support for updated ATF file format
Merge remote-tracking branch 'refs/remotes/upstream/master' into fastMathNoApparat
fixed vertex data bounds if object is empty (closes #345)
removed obsolete import statement