Unquote From line from patch before comparing with given from address.

This makes --suppress-from actually work when you're unfortunate enough
to have non-ASCII in your name.  Also, if there's a match use the optionally
RFC2047 quoted version from the email.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>