Initial work on refactoring DisplayObject

Separating the common parts from what should be implemented
in subclasses.
Initial work on a selection API

It's absolutely insane but works at least.
Better vertex buffers
Selection with mouse re-enabled
Center on selected re-enabled
Controls for setting selection mode
Components in treeview
Remove old
Feature parity after refactoring
Merge pull request #1 from TheBB/refactor

Refactor