t4013: test "git log -m --raw"

This is to ensure we won't break different diff formats when we start
to imply "-p" by "-m".

Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t4013-diff-various.sh

@@ -337,6 +337,7 @@ log -m -p --first-parent master
 log -m -p master
 log --cc -m -p master
 log -c -m -p master
+log -m --raw master
 log -SF master
 log -S F master
 log -SF -p master