cheat sheets.

 a   -- Call 'git blame' for the file for the first ancestor of the
        revision listed in the current line. Sets the content buffer to
        contain the file content at the new revision.
 A   -- Call 'git blame' for the file for the first ancestor of the
        current revision. Sets the content buffer to contain the file
        content at the new revision.
 b   -- Call 'git blame' for the file for the revision listed in the
        current line. Sets the content buffer to contain the file
        content at the new revision.
 B   -- Call 'git blame' for the file for a specific revision read from
        the minibuffer.
 c   -- Call 'git cat-file blob ...' for the revision listed in the
        current line and show the output in the `output' buffer. The
        output will not have syntax highlighting.
 i   -- Display the current state information (current revision, git
        repository path etc) in the right window.
 l   -- Call 'git log' for the revision listed in the current line and
        show the output in the `output' buffer.
 L   -- Call 'git log' for the current revision and show the output in
        the `output' buffer.
 p   -- Call 'git blame' for the file for the revision that was shown
        prior to the current one. Works only if you've used `b'
        before.
 o   -- Overwrite the file with the content of the revision listed in
        the current line. Asks for confirmation before actually
        overwriting the file.
 O   -- Overwrite the file with the content of the current
        revision. Asks for confirmation before actually overwriting the
        file.
 q   -- Exit mo-git-blame and kill all its buffers.
 s   -- Call 'git show' for the revision listed in the current line and
        show the output in the `output' buffer.
 S   -- Call 'git show' for the current revision and show the output in
        the `output' buffer.
 TAB -- Re-display the `content' buffer in the right window if it has
        replaced with the `output' buffer.
 RET -- Same as `s'.