Remove doc for logger which no longer exists
Add support for server-side JOIN command for the bot's nick to core_tracker, so that the bot knows what channels it is in when it connects to a BNC which saves channels.
Add logging config and move logging config options to it
Rename event.irc_message to event.content
Only set event.context if the command is PRIVMSG. This allows for checking if an event is a message without relying on irc_* params, and anyways plugins can use event.irc_paramlist[-1] if they want the last param for non-message events.
Merge IRCConnection into BotConnection
Split BotConnection into an abstract Connection, and an implementation IrcConnection.

Also:
- Change realname to point to cloudbot.pw
- Fix QUIT messages not being displayed when being killed
- Change conn.cmd(name, [arg1, arg2]) to conn.cmd(name, arg1, arg2)
- Add conn.action and conn.notice for non-irc-specific action/notices
Add profiling plugin for debugging