listbuffer.py, allow filtering on channel names, user count or topic [feature request]

[nsklaus]

this is a feature request for listbuffer.py, to allow it to filter on channel names, user count or channels topics.
like /fset or /script commands, that allow the user to type a string to filter out the results,
it would be nice if listbuffer would have options to reduce the list of displayed channels.
idealy, after initial download of total list of all channels, then typing: user_count 50 would reduce the list to display only channels where user_count is above 50. similarily, typing search_channel blah would reduce list to display only channels where channel name contain string "blah". same with search_topic bleh.