Parse XML output of gluster for retrieving facts

[coder-hugo]

This PR provides 2 minor fixes. The first will fix #33 by parsing the xml output of the gluster command. The second one uses ; instead of , as separator for the options in the gluster_volume_#{vol}_options fact as the comma is already used by some gluster options (e.g. auth.ssl-allow) as separator. Having such an option in use every puppet run will fail with the following error:

Evaluation Error: Error while evaluating a Function Call, (<unknown>): could not found expected ':' while scanning a simple key at line 13 column 46 at .../gluster/manifests/volume.pp:272:21