Preparing for integration into the ECS
Former-commit-id: 9ca871117d0be3d4c655225d3f3dad6b0277cdd8 [formerly 9343fd818957da74e0bb7a5715a2172eefc325e5]
Former-commit-id: 93cf58c80f0cd396211df0c95063f0ad05449e75
Renamed ParticleEmitter to ParticleSystem
Added class ParticleEmitter
(First implementation, this will probably change)
Former-commit-id: a1f80db340983da5e85cedc974dd6b24a98e25b0
Switched back to defaulted operator=(ParticleEmitter&&) since it can't
throw exception anyway
Former-commit-id: 178b040a735ef01dcda21b45a317b6c534b5782e