Bring in job_script module from LWR.

Use in the DRMAA runner. This implements the long discussed GALAXY_SLOTS logic at least for PBS/TORQUE, SLURM, and grid engine when coming through the DRMAA runner.

TODO: Rework condor, pbs, and CLI job runners to utilize this.
Refactor condor job runner.

Implement exit code handling and submission script parameters (job destination parameter <param id="submit_xxxx">yyyy</param> will be passed through as xxxx = yyyy.

Bring in LWR helper scripts to implement most of these and clean up things. Utilize job_scripts module for building script (this is what fixes exit code handling).

TODO: GALAXY_SLOTS logic still not implemented, but should be easier now.
Implement GALAXY_SLOTS logic for condor.

Just pass through submit_request_cpus as GALAXY_SLOTS if set in job_conf.xml.
PBS job runner improvements (including implementing GALAXY_SLOTS).

Rework to use get_job_file, this will enable GALAXY_SLOTS logic for the PBS runner. Bring in staging fixes found in pull request #194 from CSIRO (stephen_mcmahon_). Small PEP-8 tweaks.