Modify 'C-u Tab' binding to rotate the entire buffer
Merge pull request #9 from yryozo/prototype

Modify 'C-u Tab' binding to rotate the entire buffer
(defvar outline-minor-mode-prefix "\C-c") outcommented, since it does not
really take effect here (must be set in init-file before outline is loaded)
and "\C-c" conflicts with other important modes, e.g ESS.