Connect to an IRC server, with optional security upgrade

This module is required in order for Erebot to work properly.
You should probably always install it.
It sends credentials to the server whenever the bot connects.

It also supports the STARTTLS extension (security upgrade),
which can be used to connect to an IRC server on a port
shared by both plain-text and encrypted connections.
Set the "upgrade" paramater to "1" in the connection URL
to make use of this feature.
Eg. "irc://irc.example.com?upgrade=1"

Please note that Secure IRC connections (IRCS) do not have
any need for that "security upgrade" feature, as they are
already encrypted when established.