When submitting to P4, if git-p4 came across a symlinked
directory, then during the generation of the submit diff, it would
try to open it as a normal file and fail.
Spot symlinks (of any type) and output a description of the symlink
instead.
Add a test case.
Signed-off-by: Luke Diamand <luke@diamand.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>