Downgrade git-send-email-script

RPM folks have problem installing the package otherwise.  Since
its usefulness does have much to do with GIT, downgrade it to
"contrib" status for now.  We may want to move it to contrib/
subdirectory after auditing other programs when we reorganize
the source tree.

Signed-off-by: Junio C Hamano <junkio@cox.net>

Makefile

@@ -69,7 +69,7 @@ SCRIPTS=git git-apply-patch-script git-merge-one-file-script git-prune-script \
 	git-request-pull-script git-bisect-script
 
 SCRIPTS += git-count-objects-script
-SCRIPTS += git-send-email-script
+# SCRIPTS += git-send-email-script
 
 PROG=   git-update-cache git-diff-files git-init-db git-write-tree \
 	git-read-tree git-commit-tree git-cat-file git-fsck-cache \