mod_block_registrations: Support blocking confusable usernames (UTS 39) This prevents registering e.g. "admin" but with a Cyrillic 'a' U+0430 and other such variations, including keming like "adrnin".

This module produces more detailed HTTP logs for Prosodys built-in HTTP
server. The format is similar to that of Apache and go into Prosodys
normal logs at the `info` level.