Implemented crude channels
- CHCH-2 :
- Created ChibiChat::Channel to store channel membership and settings
- Added function to register channels on a ChibiChat::Server
- Added configuration parsing code for channels to reference server
- CHCH-4 :
- Created Channel Myon class to parse/generate channel related messages
- Added minimal GUI additions to join/part channels from the reference client
- Added code to handle joins/leaves
- Misc:
- Renamed ChibiChat::Element to ChibiChat::Myon to create uniform naming
- Added Shared and Weak pointers to manage clients and channel instances