Added BitmapDrawable. WIP DrawableInstance draw method.
Removed un-needed GetSourceTexture from IGameDrawable interface.
Added GetWidth and GetHeight interface methods.
Moved Drawing logic to GameDrawableInstance and refactored interface.
Refactoring so that individual Layer properties in drawables are
calculated internally instead of externally.
Placed ShowDrawableComponents draw code outside of GameDrawableIntance
Renamed GameDrawableInstance to DrawableInstance.
Updated TASKS.
Merge branch 'ImprovedDrawingStructure'