helpers

docs, explaining what this arguments are for

noconfirm_close_muc_rooms is too much customizability exposed to user which only ends up confusing him. fixes #1622

error / not_in_roster / requested / message icons are no more taken in transporticonset, but in jabber iconset. Fixes #1250

noconfirm_close_muc_rooms to say that list wants to be space seperated {should be our default way} and desc to finish with dot.