Applied learno's gundo_disable patch -- https://bitbucket.org/sjl/gundo.vim/issue/33/let-g-gundo_disable-0-is-not-available
Issue34 - The graph now shows marks nodes written to disk with a 'w'.
Updated vim docs.
Added live reload of the undo buffer as you edit the file. Courtesy of
Patrick Oscity
(https://bitbucket.org/sjl/gundo.vim/issue/40/feature-request-live-reload).