mod_cloud_notify: Identify (and immediately push) urgent stanzas, e.g. calls This covers the following things: - A session that appears online, but has a broken TCP connection - Clients such as Siskin and Snikket iOS that require a push for calls to work It allows the stanza to be pushed immediately instead of waiting for the session to hibernate or an ack to timeout. It shouldn't break any existing cases.

This module discards typing notifications sent to a bare host JID,
preventing error replies to be sent. These errors are harmless but can
be annoying sometimes if your client shows them prominently.