Changed Particle system to fluids for interparticle collision.
circle shaped particles
add water particle normals rendering step #30
set viewport uniform, use RGB attachment for normals #30
add normals #30
add bluring + edge sensitive normal calculation
correct normal calculation
terrain shadow map #18
Minor changes.
Merge remote-tracking branch 'remotes/origin/master' into physical_correct_particles

Conflicts:
	src/particleemitter.cpp
	src/particleemitter.h
Merge branch 'master' into water_rendering_30
really correct normals
F changes between emitters. (No visible changes) and emitters emit particles when left mouse button is held down.
improved depth calculation
right normals
add water depth blurring step, move some rendering steps to subclass of RenderingStep #30
Merge branch 'water_rendering_30' into shadow_mapping_18

Get the rendering step refactoring.

Conflicts:
	CMakeLists.txt
	src/rendering/renderer.cpp
	src/rendering/renderer.h
move implementation to shadowmapping class #18
linearize depth #18
copypaste shadowmapping from cgsee #18