mod_rest: Use logger of HTTP request in trunk In Prosody trunk rev c975dafa4303 each HTTP request gained its own log sink, to make it easy to log things related to each request and group those messages. Especially where async is used, spreading the request and response apart as mod_rest does with iq stanzas, this grouped logging should help find related messages.

Over the years, some servers stop working for various reasons, and leave
behind broken roster subscriptions that trigger failing s2s connections.
This module allows cleaning up such cases by unsubscribing local users
from their contacts on those servers. Also works for typos and the like.
Use with care.

```lua
Component "gmail.com" "unsubscriber"
```