Merge branch 'stable-2.7' into stable-2.8

* stable-2.7:
  Update NEWS with disk creation fixes
  Don't fail to deactivate master IP if already down
  Add QA for recreating single instance disks
  Add QA for gnt-instance modify --disk
  Clean up when "gnt-instance modify" fails to create a disk
  recreate-disks honors the prealloc_wipe_disks flag
  Introduce wrapper for cmdlib._WipeDisks()
  Don't catch an exception that cannot be raised
  Wipe disks added through "gnt-instance modify"
  Support /var/run being a symlink in upload
  Final NEWS and configure.ac update for 2.7.0~rc1
  gnt-job list: deal with non-ascii encoding in jobs

Conflicts:
	NEWS
	lib/cmdlib.py
	qa/ganeti-qa.py
	qa/qa-sample.json

NEWS, qa/ganeti-qa.py and qa/qa-sample.py had trivial conflicts. But I've
updated QA changes to use the new interfaces. lib/cmdlib.py was renamed and
split, so I had to semi-manually apply the changes to the new files. I had
to change the names of some functions by removing or adding the initial
underscore and update the imported names.

Signed-off-by: Bernardo Dal Seno <bdalseno@google.com>
Reviewed-by: Thomas Thrainer <thomasth@google.com>