* lisp/net/rcirc.el (rcirc-server-parameters): New variable (bug#6795).
(rcirc-connect): Set it.
(rcirc-handler-433): Use the length from the server.
(rcirc-handler-005): Collect server data.
(rcirc-server-parameter-value): New utility function.
(rcirc--make-new-nick): New function.