[PATCH] diff: code clean-up and removal of rename hack.

[PATCH] diff: code clean-up and removal of rename hack.

A new macro, DIFF_PAIR_RENAME(), is introduced to distinguish a
filepair that is a rename/copy (the definition of which is src
and dst are different paths, of course).  This removes the hack
used in the record_rename_pair() to always put a non-zero value
in the score field.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>