We already use the normalization from get_pathspec(), but now we also
remove a trailing slash. So,
git mv some_path/ into_some_path/
works now.
Also, move the "can not move directory into itself" test before the
subdirectory expansion.
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>