Draw only on-screen objects.
Use tilesets instead of single pictures for each tiles.
Merge branch 'feature/Rendering_optimzation' into develop
Added a new resources holder (replate TextureCache).
Project file updated.
Added SoundEvent.
Added a resources holder for SoundBuffers.
Added the SoundSystem.
Project file updated.
Added new sounds.
Added CSoundSource, component containing the entity's sounds. Each entity can have its own sounds (each sound is named)
Merge branch 'feature/SoundSystem' into develop
Clean the code of useless #includes.
Removed the split-screen mode.
Use standard C++11 conversions and remove Boost dependency (still used by entityx).
Fixed a bug with arguments misinterpreted.
Renamed Scene to GameState.
Game engine now manages all states.
Can push or pop a state.
Added shared data container in GameEngine. Removed StateArguments.