Allow ban/invite/exception short replies

Allow replies with only 2 arguments in ban/invite/exception lists.
RFC2812 specify only two arguments, ban owner and set date are extensions.
Fix duplicate entries in banlist window

If user is pressing hotkey of list window too fast there is duplicate entries
in list.
Allow to see ban/exception/invite list by command

This commit allows user to see channel mode lists using both UI and
commands like "/mode #channel +I" in server window.
Closes #456 with a few slight modifications.