Use parentheses and `...' where appropriate

Remove some stray usage of other bracket types and asterisks for the
same purpose.

Signed-off-by: Štěpán Němec <stepnem@gmail.com>
Acked-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/fetch.c

@@ -16,7 +16,7 @@
 static const char * const builtin_fetch_usage[] = {
 	"git fetch [<options>] [<repository> [<refspec>...]]",
 	"git fetch [<options>] <group>",
-	"git fetch --multiple [<options>] [<repository> | <group>]...",
+	"git fetch --multiple [<options>] [(<repository> | <group>)...]",
 	"git fetch --all [<options>]",
 	NULL
 };