Feature/sge workers

Finally done! 
This pull request is a superset of #6 

This allows the vagrant scripts to provision SGE workers nodes with a working install of oozie-sge plugin and a fix to NFS (which is needed for a shared filesystem). This was tested with 1.0.7 and successfully runs on OpenStack (with one master and one worker, working through issues with IT). SGE submissions are verified to successfully distribute between the master and the worker.

Note that integration tests may fail, they currently write some information to /tmp which is not shared, but is something that will have to be fixed (however, is outside the scope of this repo.)