Fixes to thes pbs send script

Fixes to thes pbs send script

util/pbs/send.py:
    - add a -d to set the job root directory allowing one to run
    send.py from anywhere.
    - specify full paths to files instead of relative paths to make -d
    work and to allow ssh qsub to work again.
    - make the Link directory only copy links that point to regular files.

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extra : convert_revision : dd330cee08b97c5d72c3d58ef123f83ac7ccede7