mod_net_proxy: Use safer util.format for generating description string (thanks tom) It appears that server_event may emit port numbers (src_port() in this case) as strings, rather than integers. This causes string.format() to throw an error. Prosody's util.format is a more forgiving formatter and won't throw an error. The server_event behaviour may be best fixed for the sake of consistency, though.

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labels:
- 'Stage-Alpha'
summary: Implements BOSH pre-bind
...

For why this can be useful, see
https://metajack.im/2009/12/14/fastest-xmpp-sessions-with-http-prebinding/

# To enable this module

Add `"http_prebind"` to `modules_enabled` on an anonymous virtual host.

This only works on anonymous ones for now.