* stable-2.12
  QA: Fix CheckFileUnmodified to work with vcluster
  QA: Fix white-spaces in CheckFileUnmodified
  QA: Check that the cluster verify doesn't change the config
  QA: Allow to check that an operation doesn't change a file
  Use only shared configuration lock for ComputeDRBDMap
  Only assert properties of non-None objects
  If any IO error happens during job forking, retry
  Add a function for retrying `MonadError` computations

* stable-2.11
  Improve speed of Xen hypervisor unit tests
  Improve Xen instance state handling

* stable-2.10
  Make QA fail if KVM hotplugging fails
  Always preserve QA command output
  Don't lose stdout/stderr in AssertCommand
  qa_utils: Allow passing fail=None to AssertCommand
  qa_utils: Make AssertCommand return stdout/stderr as well
  Allow plain/DRBD conversions regardless of lack of disks
  Add support for ipolicy modifications to mock config

Conflicts:
	lib/cmdlib/instance.py - propagate changes from 2.12
	qa/qa_cluster.py - propagate changes from 2.12
	qa/qa_instance.py - propagate changes from 2.12
	qa/qa_utils.py - propagate changes from 2.12
	src/Ganeti/Utils/Monad.hs - merge changes from both branches

Signed-off-by: Petr Pudlak <pudlak@google.com>
Reviewed-by: Hrvoje Ribicic <riba@google.com>