git-commit.txt: (synopsis): move -i and -o before "--"

All options, including -i and -o, must come before "--" which is the
end of options marker.

Reported-by: Joey Hess <joey@kitenet.net>
Signed-off-by: Jari Aalto <jari.aalto@cante.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-commit.txt

@@ -11,8 +11,8 @@ SYNOPSIS
 'git commit' [-a | --interactive] [-s] [-v] [-u<mode>] [--amend] [--dry-run]
 	   [(-c | -C) <commit>] [-F <file> | -m <msg>] [--reset-author]
 	   [--allow-empty] [--allow-empty-message] [--no-verify] [-e] [--author=<author>]
-	   [--date=<date>] [--cleanup=<mode>] [--status | --no-status] [--]
-	   [[-i | -o ]<file>...]
+	   [--date=<date>] [--cleanup=<mode>] [--status | --no-status]
+	   [-i | -o] [--] [<file>...]
 
 DESCRIPTION
 -----------