refactoring + style fixes OpenFOAM easyblock
add ported and enhanced easyblock for MUMPS
pick correct WM_MPLIB value for OpenFOAM-ext with goolf
merge two very similar if-elif-else blocks
get rid of senseless value for $WM_MPLIB in case of OpenMPI build
make sure dependencies are picked up by setting proper premakeopts
Revert "get rid of senseless value for $WM_MPLIB in case of OpenMPI build"

This reverts commit 8bd2fba6363171d2efe767264e48cd03c9027a9d.
add support for building/installing OpenFOAM-Extend
Merge branch 'develop' into openfoam_mumps
fix sanity check for OpenFOAM v2.3.0
correct setting for WM_MPLIB for OpenMPI-based toolchains + add matching comment
simplify check for OpenFOAM-Extend
fix sanity check for OpenFOAM-Extend, use run_cmd_qa for OpenFOAM-Extend configuration
fix determining OpenFOAM subdir for OpenFOAM-Extend versions prior to 3.0
Merge pull request #253 from boegel/openfoam_mumps

code style fixes in OpenFOAM easyblock