merge-recursive --renormalize

merge-recursive --renormalize

Teach "git merge-recursive" a --renormalize option to enable the
merge.renormalize configuration.  The --no-renormalize option can
be used to override it in the negative.

So in the future, you might be able to, e.g.:

	git checkout -m -Xrenormalize otherbranch

or

	git revert -Xrenormalize otherpatch

or

	git pull --rebase -Xrenormalize

The bad part: merge.renormalize is still not honored for most
commands.  And it reveals lots of places that -X has not been plumbed
in (so we get "git merge -Xrenormalize" but not much else).

NEEDSWORK: tests

Cc: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>