update to 5.0.4
- switch Motif library to original Motif (as it's in Fedora since long)
- link against new-style atlas library (atlas 3.10.1+)
- BR: boost-devel
- csh/zsh completion removed upstream
- move bash completion into main package
- separate ngmx and mdrun dropped upstream
- enable testsuite
- factorize a lot of build logic
- drop redundant comments