Cleanup ncar resource file.
Add support for MPI on LSF by means of POE (e.g. yellowstone).
For LSF get number of cores from environment, and not by counting cores.
Some comments too.
Major refactoring, mainly in the slot acquisition.
Has a better abstraction now.
Merge branch 'devel' into feature/mpi

Conflicts:
	src/radical/pilot/configs/ncar.json
Run on multiple nodes by default, cleanup unused ssh creds and some
documentation.