remote: fix set-branches usage and documentation

The canonical order of command line arguments is always to have dashed
commands before other parameters, but the "git remote set-branches"
subcommand was described to take "name" before an optional "--add".

Signed-off-by: Philip Jägenstedt <philip@foolip.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/remote.c b/builtin/remote.c
index 06741ec..7f3514b 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -16,7 +16,7 @@
 	"git remote [-v | --verbose] show [-n] <name>",
 	"git remote prune [-n | --dry-run] <name>",
 	"git remote [-v | --verbose] update [-p | --prune] [group | remote]",
-	"git remote set-branches <name> [--add] <branch>...",
+	"git remote set-branches [--add] <name> <branch>...",
 	"git remote set-url <name> <newurl> [<oldurl>]",
 	"git remote set-url --add <name> <newurl>",
 	"git remote set-url --delete <name> <url>",