m_exemptchanops Fix parameter validation
Change ListModeBase::DoRehash() to not be virtual
Remove a bunch of useless classes representing simple core modes
Pass prefix rank and prefix char to PrefixMode constructor
Migrate ModeChannelOp and ModeChannelVoice constructors to builtinmodes.h, remove cmode_{o,v}

The default value for levelrequired is HALFOP_VALUE, meaning the ModeChannelVoice class is not required but it will be useful in case the default changes
m_ojoin Leave it to the core throw an exception if the prefix char is in use
m_ojoin Change allocation of NetworkPrefix to be physically part of the object containing it
Add header for TOTP
Add module for providing TOTP service
Add module for requiering TOTP on oper blocks