mpi functions now used properly (e.g. sendrecv instead of send+recv);
benchmark now excludes debug gather;
internal reference solutions for comparison in every mpi project
Merge branch 'master' of github.com:Animiral/ParComp5

Conflicts:
	mpi/project1/stencil
	mpi/project2/prefix-sums
	mpi/project3/allgather
	mpi/project3/reduce-scatter