karpark/jbox2d — pull request #8 by karpark (2014-04-24 08:33:12+00:00)
Title: Selection Manager implementation

Also, wrappted raw box2d object so that we can manipulate better.
Rather big change, and this sets a path on how we will keep building
the remaining works.

Inheritance hierarch
Body -- GraphSelectableObject -- GraphObject -- Vertex
Body -- GraphSelectableObject -- GraphObject -- Edge

GraphSelectableObject implements interface ISelectable, so that SelectionManager can select/deselect them.