mod_debug_traceback: Remove direct POSIX signal handling, require Prosody 0.12+
Hooking an event is safer than directly hooking signals
For context see Prosody trunk rev 69faf3552d52
This module allows advertising a machine-readable document were outages,
planned or otherwise, may be reported.
See [XEP-0455: Service Outage Status] for further details, including
the format of the outage status document.
```lua
modules_enabled = {
-- other modules
"service_outage_status",
}
outage_status_urls = {
"https://uptime.example.net/status.json",
}
```
The outage status document should be hosted on a separate server to
ensure availability even if the XMPP server is unreachable.