Add instructions how to redo/finish failed merge with local working directory.
b2ae81a7df29 already implemented this for branch merges.
adding dir/bar
adding foo
dir/bar
foo
adding dir/bar_2
adding foo_2
dir/bar_2
foo_2
adding a
adding c
adding b
adding d
removing a
removing c
recording removal of a as rename to b (100% similar)