Preparing for integration into the ECS
Former-commit-id: 201e28c9f00ee31f809d9de3d9a37f57a7fe740c [formerly 9b88616308f9801482fc8811a9a19a7231dce2a7]
Former-commit-id: 579f4e9597f94620f922fb145931202d8fc9cc96
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