mod_log_ringbuffer: Detach event handlers on logging reload (thanks Menel) Otherwise the global event handlers accumulate, one added each time logging is reoladed, and each invocation of the signal or event triggers one dump of each created ringbuffer.

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

``` {.lua}
modules_enabled = {
    -- other modules --
    "s2s_whitelist",

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