Merge branch 'next' into branch-2.1

Merge branch 'next' into branch-2.1

* next:
  Create a new --no-voting option for masterfailover
  ganeti-masterd: allow non-interactive --no-voting
  Fix pylint warnings
  Add custom pylintrc
  bootstrap: Don't leak file descriptor when generating SSL certificate
  Fix problem with EAGAIN on socket connection in clients
  Fix some typos
  Increase maximum accepted size for a DRBD meta dev
  Cleanup config data when draining nodes
  Fix node readd issues
  backend.DemoteFromMC: don't fail for missing files
  Allow GetMasterCandidateStats to ignore some nodes
  Fix error message for extra files on non MC nodes

Conflicts:

	lib/backend.py
          Most of the conflicts where in the new rpcs VS pylint fixes
          and usually the new rpcs fixed the pylint problems as well
	lib/bootstrap.py
          Small conflict between masterfailover --no-voting and new rpcs
	lib/cmdlib.py
          Net parameters conflicted here, kept that version
	lib/objects.py
          Same problem fixed in two different ways. 'next' version kept

Signed-off-by: Guido Trotter <ultrotter@google.com>