[vdsm] PEP8 in VDSM code

I suggest having pep8 a must for patch submission in VDSM.
http://www.python.org/dev/peps/pep-0008/

Currently there are a few people policing these rules in reviews but I suggest we make it automatic.

Unless someone objects I will put a gerrit hook that complains about pep8 violations.
It will not mark -1s until all (or at least most) source code has been converted because people might get complains about code they did not modify in this patch.

If you happy and you know it +1!