add MPI launcher script (bash)

Signed-off-by: Sebastien Varrette <sebastien.varrette@uni.lu>
update README accordingly

Signed-off-by: Sebastien Varrette <sebastien.varrette@uni.lu>
Merge branch 'devel' of github.com:ULHPC/launcher-scripts into devel

# By Fotis Georgatos
# Via Fotis Georgatos
* 'devel' of github.com:ULHPC/launcher-scripts:
  Create softwaretools.md