standardize usage info string format

This patch puts the usage info strings that were not already in docopt-
like format into docopt-like format, which will be a litle easier for
end users and a lot easier for translators. Changes include:

- Placing angle brackets around fill-in-the-blank parameters
- Putting dashes in multiword parameter names
- Adding spaces to [-f|--foobar] to make [-f | --foobar]
- Replacing <foobar>* with [<foobar>...]

Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/check-attr.c

@@ -8,8 +8,8 @@ static int all_attrs;
 static int cached_attrs;
 static int stdin_paths;
 static const char * const check_attr_usage[] = {
-N_("git check-attr [-a | --all | attr...] [--] pathname..."),
-N_("git check-attr --stdin [-z] [-a | --all | attr...] < <list-of-paths>"),
+N_("git check-attr [-a | --all | <attr>...] [--] <pathname>..."),
+N_("git check-attr --stdin [-z] [-a | --all | <attr>...] < <list-of-paths>"),
 NULL
 };