clone-pack: remove unused and undocumented --keep flag

While we are at it, give fully spelled --keep to fetch-pack.
Also give --quiet in addition to -q to fetch-pack as well.

Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/fetch-pack.c b/fetch-pack.c
index 2528053..d34f322 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -416,11 +416,11 @@
 				exec = arg + 7;
 				continue;
 			}
-			if (!strcmp("-q", arg)) {
+			if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) {
 				quiet = 1;
 				continue;
 			}
-			if (!strcmp("-k", arg)) {
+			if (!strcmp("--keep", arg) || !strcmp("-k", arg)) {
 				keep_pack = 1;
 				continue;
 			}