abstract superclass Drawable, also for ParticleDrawable, adding boudingbox to all drawables #92
add bounding box rendering step, shader unfinished #92
draw bounding boxes as grid #92
toggle drawing of "debugstep" with key F1 #92
Merge branch 'project_reordering' into particleCollision_92

Conflicts:
	CMakeLists.txt
	src/rendering/drawable.cpp
	src/rendering/renderer.cpp
	src/ui/eventhandler.cpp
	src/ui/hand.cpp
	src/world.cpp
implement basic bbox based collision check #92
perform collision check only 2x per second #92
create lua script for the collision handling #92
get and visualize the particle boundingbox intersection volumes #92
nicer boxes with back face culling #92
improve bounding box based collision detection #92

good result, if only a single set of colliding particles exists between two particle groups
add more int types to supported lua parameter types
particleGroup: release particles in bounding box, create particles without velocities, use std::vector #92
first element reaction: lava+water=bedrock #92 #63
improve bounding box based collision, again #92
Merge remote-tracking branch 'origin/master' into particleCollision_92
move elemate code to separate library, add sub projects for the scripts and shader #114
integrate google test #114
add simple game test as example, producing linker errors #114, #115
upgrade to glow 0.3.0 #115