BigJob Implementation for clouds:

- Currently only support for Nimbus - Nimbus must be separately installed (see http://workspace.globus.org/clouds/nimbus.html)
- Configurations (currently still on top of bigjob_cloud.py):

NIMBUS_CLIENT="/opt/nimbus/bin/cloud-client.sh"
NIMBUS_URL="nimbus://tp-vm1.ci.uchicago.edu"
IMAGE_NAME="gentoo-saga-1.3.3.gz"
DEFAULT_WALLTIME=60   #in minutes

- Run Example:

python example-cloud.py