Create a name -> ModeHandler* map
Add a ModeParser::FindMode() overload that takes a mode name and a mode type
Replace mode letter parameter of OnRawMode() with a ModeHandler*, remove pcnt
Assign an id to user modes, parameter chanmodes and simple chanmodes
Index Channel::modes and User::modes with the id of the mode instead of its letter
Add ModeParser::GetModes(), returns all user/chanmodes