Merge branch 'config' into diffusion

Conflicts:
	.gitignore
	examples/CMakeLists.txt
	examples/heat-equation/CMakeLists.txt
	examples/simple-solver/CMakeLists.txt
	examples/simple-solver/simple-solver.cfg.desc
	examples/simple-solver/simpleProblemSetter_impl.h
	src/implementation/mesh/tnlGrid3D_impl.h