mod_post_msg: Add sendxmpp-curl I wrote this script around the same time as this module. My local copy has a last modification timestamp of 2011-03-29, so it's been unchanged since then. The original rationale was that it seemed overkill to establish an entire XMPP session just to send a single message. Nowadays I'm quite happy using `clix` for this kind task.

This module lets you block connections to any remote servers not on a
whitelist.

``` {.lua}
s2s_whitelist = {
    "example.org",
}
```