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/merge-base.c

@@ -26,8 +26,8 @@ static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 }
 
 static const char * const merge_base_usage[] = {
-	N_("git merge-base [-a|--all] <commit> <commit>..."),
-	N_("git merge-base [-a|--all] --octopus <commit>..."),
+	N_("git merge-base [-a | --all] <commit> <commit>..."),
+	N_("git merge-base [-a | --all] --octopus <commit>..."),
 	N_("git merge-base --independent <commit>..."),
 	N_("git merge-base --is-ancestor <commit> <commit>"),
 	N_("git merge-base --fork-point <ref> [<commit>]"),