Added NYU HPC support

batchq/bin/functions:
- NYU HPC qsub needs "qsub start.pbs", not "cat start.pbs > qsub"

batchq/contrib/vistrails/RemotePBS/init.py:
- Added port attribute to Machine

batchq/pipelines/shell/ssh.py:
- Ignore port when port=0 so that ssh aliases works
- Automatically detect passwordless login