protocol/charybdis: start adding new protocol handling code
src/cod: add variable stub
src/protocol: Add new outbound TS6 protocol handler
protocol/inspircd: New protocol handling
src/protocol: Add function for parting channels
protocol: Use protocol handlers
protocol/inspricd: upgrade to nextgen handling
Merge branch 'better-protocol-handling'

As part of the move to allow nick-based protocols.