Merge branch 'devel-2.6' into master

* devel-2.6:
  htools-excl.test: add test case for exclusion tags in hbal
  Instance.hs: rename 'tags' to 'exclTags', provide 'allTags'
  Group.hs: add 'allTags'; adjust loaders and test data for it
  Add hbal-excl-tags.data to Makefile.am, missed in 0397694e

Conflicts:
	Makefile.am: hbal-excl-tags.data moved under htest/
	htools/Ganeti/HTools/Luxi.hs: types from Qlang are now used
	htools/Ganeti/HTools/QC.hs: defGroup definition now in TestHTools.hs
	lib/cmdlib.py: IAllocator class now in iallocator.py
	test/htools-excl.test: moved under htest/

Signed-off-by: Dato Simó <dato@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>