mod_audit: Fix recording location info The method :query_by_addr only works for IPv4, even if you open the IPv6 database, which is an odd API. It also returns a table, not a string.

This module blocks configured queries that change server state.

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

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