Bringing gce_condor up to date.

Hi Jose,

Thanks for writing gce_condor - it was a great quick way to get a condor cluster up and running!  I found that I needed to make a few tweaks for everything to work since some dependencies have changed a bit.  Here's a patch with those tweaks.

- Nicole

(1) Upgraded to oauth2client.tools.run_flow from deprecated oauth2client.tools.run.
(2) Added workaround for apt-get install issue with condor dependency upon libvirt0.
(3) Fixed minor typo in documentation.