Attached patch suppresses byte compiler warnings.
Most changes are to replace (require 'cl) with (require 'cl-lib). Few other changes were also made simply by following messages printed by the byte compiler, e.g., replacing show-branches with outline-show-branches, org-pop-to-buffer-same-window with pop-to-buffer-same-window, and declaring new-of as a dynamic variable to prevent it from being a free variable.