Improvements for ban/invite/exception lists

This patchset removes the following limitations in mode lists handling:

1) RFC2812 allows replies with only 2 parameters but Textual requires 4 (that is an extension).
2) When user is pressing Cmd-Shift-B and too fast after connecting to the server, there will be duplicate entries in list
3) Commands like "/mode #channel b" does not work, currently lists can only be displayed using UI. Change behaviour to behaviour of command like "/who" - when it is invoked by user, print reply.