Changed Particle system to fluids for interparticle collision.
Minor changes.
Merge remote-tracking branch 'remotes/origin/master' into physical_correct_particles

Conflicts:
	src/particleemitter.cpp
	src/particleemitter.h
F changes between emitters. (No visible changes) and emitters emit particles when left mouse button is held down.
Introducing descriptionData concept to create new ParticleEmitter instances without calling a load of functions through PhysicsWrapper. Integrated this concept and sound-data into "elements.h/cpp". Not every description data takes effect and sound position is still incorrect.
Set hand back down.
Merge remote-tracking branch 'remotes/origin/master' into physical_correct_particles

Conflicts:
	src/physicswrapper.cpp
Merge pull request #78 from lanice/physical_correct_particles

Physical correct particles pull request