In my haste in setting up the new light proxy, I neglected to account for the fact that they must now be added to the world to function.
Merge branch 'master' of https://github.com/BlackToppStudios/Mezzanine
Set an initializer for the "InWorld" bool on renderable proxies.
Implemented all non-serialization methods and support classes for billboards.
Renamed some serialization variables to be more descriptive.
Implemented serialization code for the billboard class.
Implemented serialization methods for the BillboardSetProxy class.
Added creation methods for BillboardSetProxy to the SceneManager.
Merge branch 'master' of https://github.com/BlackToppStudios/Mezzanine