mod_report_forward: Fix traceback on error message passed to datetime function If archive:get() returns an error, e.g. because it can't find a message with the given ID, it may return e.g. nil, "item-not-found" or similar where the error condition ends up in reported_message_time, which gets passed to util.datetime, which thus ends up doing math to a string or error object.

---
labels:
- 'Stage-Alpha'
summary: 'XEP-0033: Extended Stanza Addressing'
...

Introduction
============

This module is a partial implementation of [XEP-0033: Extended Stanza
Addressing](http://xmpp.org/extensions/xep-0033.html).

TODO
====

Query external servers for support.