Merge branch 'devel-2.1'

Merge branch 'devel-2.1'

* devel-2.1:
  utils: Add class to split string stream into lines
  Fix cluster behaviour with disabled file storage
  Update docstrings in tools/ and enable epydoc
  Forward-port the ganeti 2.0 cfgupgrade
  Add a new tool: sanitize-config
  Fix cfgupgrade with non-default DATA_DIR
  Improving the RAPI documentation
  Mark cluster-merge as executable
  QA: Make the rapi credential handling less involving

Conflicts:
	lib/bootstrap.py (merge cds and new file names)
	lib/cmdlib.py    (trivial, kept 2.1 version for disabled file
	                  storage)
	lib/utils.py     (trivial, new imports)
	tools/cfgupgrade (trivial, new cds parameter)

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>