fixes LIBS-51
Sprite's hit test checks graphics area before of children
http://jangaroo.myjetbrains.com/youtrack/issue/LIBS-51

Reversing check order.
On the fly, giving a Sprite's canvas element the attribute
data-flashclass="flash.display.Graphics" for debugging.
fixes LIBS-52
Shape DOM representation lacks position:absolute style
http://jangaroo.myjetbrains.com/youtrack/issue/LIBS-52

A call to updateTransform() was missing in Shape's
overridden updateElement() method, which on purpose
does not call super.updateElement().
fixes LIBS-53
Removed DisplayObjectContainer child elements not removed from DOM
http://jangaroo.myjetbrains.com/youtrack/issue/LIBS-53

Impossibly many stupid bugs in the check for unchanged DOM
structure. Need unit tests!