Better pool job handling

Better pool job handling

util/pbs/job.py:
    the default jobfile is now Test.py in the root of the jobs directory
util/pbs/pbs.py:
    Clean up the qsub options handling and add job dependencies
util/pbs/send.py:
    the default jobfile is now Test.py in the root of the jobs directory
    add a flag to depend on your checkpoint
    add a flag to specify your node type
    create the base directory if it doesn't exist

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extra : convert_revision : dfffa4a5b0e68b2550a28fbb06b9d6a208ea1f2e