Remove mpiexec.hydra from keys in Launcher dictionary
Remove mpiexec.hydra from keys in Launcher dictionary

- Dictionary keys are expected to uniquely identify launchers
  mpiexec and mpiexec.hydra for example are ambiguous as
  multiple MPI implementations alias this binary name.

Change-Id: Ifb2e2f7573e00e3bd69f9d8a22c8268d695a4761
Signed-off-by: Brandon Baker <a57ed95460e44c7b5dd675b778bcd98e47bd07ea@intel.com>

cmcantalupo/geopm,cmcantalupo/geopm,cmcantalupo/geopm,cmcantalupo/geopm,geopm/geopm,geopm/geopm,geopm/geopm,cmcantalupo/geopm,geopm/geopm,geopm/geopm