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
keep the hand above the terrain #77
add height offset between Hand and Terrain #77

- let the hand fetch the height information from the terrain directly
- make transform/height calculations lazy
include <string> in hand.h. #77
allow toggling vsync with Key V #82
implement early bailing + general shadowing improvements #82
fix sampler uniform type #82
fetch physx data only when needed #82
fetch height at hand position when scene fbo is bound while rendering #82
fix TerrainTile bind/unbind #82
fix major performance problem: call TerrainTile::initialize() only once #82

do not load the rock.raw in every frame..
Merge pull request #81 from lanice/Fix_HandPosition_77

Fix hand position 77
remove fma for glsl 330 compatibility #82