workaround to fix camera movement
add OGLplus submodule - C++ wrapper around OpenGL
separate cube rendering from window class
remove debug prints
add sphere renderer
refactoring
rename particles_renderer class files
shaders sources moved to particle_renderer.cpp + fix compilation errors
Merge branch 'dev/visualizer_glfw_spheres' into dev/visualizer_glfw

Conflicts:
	visual/CMakeLists.txt
	visual/visualizer.cpp