examples/public-inbox.psgi: add usage to comments

I often forget how to run this

diff --git a/examples/public-inbox.psgi b/examples/public-inbox.psgi
index 6d8fd24c49a0c8b2e511bb3cfcb191a4fc45e892..8eb67eb182fb01641565dd0932258760709b366c 100644 (file)
--- a/examples/public-inbox.psgi
+++ b/examples/public-inbox.psgi
@@ -2,6 +2,7 @@
 # Copyright (C) 2014, Eric Wong <normalperson@yhbt.net> and all contributors
 # License: AGPLv3 or later (https://www.gnu.org/licenses/agpl-3.0.txt)
 # Note: this is part of our test suite, update t/plack.t if this changes
+# Usage: plackup [OPTIONS] /path/to/this/file
 use strict;
 use warnings;
 require PublicInbox::WWW;