cherry-pick/revert: make usage say '<commit-ish>...'

The usage string for cherry-pick and revert has never been updated to
reflect their ability to handle multiple commits. Other documentation is
already correct.

Signed-off-by: Kevin Bracey <kevin@bracey.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/revert.c

@@ -19,13 +19,13 @@
  */
 
 static const char * const revert_usage[] = {
-	N_("git revert [options] <commit-ish>"),
+	N_("git revert [options] <commit-ish>..."),
 	N_("git revert <subcommand>"),
 	NULL
 };
 
 static const char * const cherry_pick_usage[] = {
-	N_("git cherry-pick [options] <commit-ish>"),
+	N_("git cherry-pick [options] <commit-ish>..."),
 	N_("git cherry-pick <subcommand>"),
 	NULL
 };