This reverts commit 7396fc84.

This turns a package into a branch of another package, after the fact.

Do not filter Compiler for CUDA repositories, they have a fixed
relationship, change macro semantic somewhat, add have_* macros

Has a (hopefully) less confusing syntax now, option to directly restrict
set of compiler/MPI/CUDA modules from commandline

An alias is in place to also provide the old name

This seems to be an OBS bug

and some internal re-orginisation