Merge branch 'develop' of github.com:hpcugent/easybuild-easyconfigs into develop
use --disable-dlopen to avoid problems like with Rmpi 'lib/openmpi/mca_paffinity_hwloc.so: undefined symbol: opal_hwloc_topology', and use correct configure flag to enable MPI threading suport
correct configure flag for MPI threading support
Merge pull request #186 from boegel/openmpi_fixes

add --disable-dlopen, use correct configure flag for MPI threading support