mod_ping_muc: Delay ping a configurable amount of time If a server is restarting, checking immediately before it has a chance to complete its restart and get ready would often fail, preventing the possibility of transparent restarts as supported by Prosody's mod_muc. Reconnecting immediately when a connection is closed for being idle, or because the remote server is trying to reclaim some resources, is also counter-productive as the connection may fail. Also, if there is some Internet routing problem affecting s2s, it may help to wait a bit before checking, in case the problem resolved itself in the mean time.

This module blocks configured queries that change server state.

E.g. to make vCard storage read-only:

``` lua
readonly_stores = {
	vcard = { "vcard-temp", "vCard" };
}
```