This reworks per-connection parsed_queues into one bot.queued_messages queue.

List of all changes:

- Renames cloudbot.start_bot() to cloudbot.start(), and makes it start IRC connections there as well
- Reworks the main cloudbot loop in cloudbot.start() to just use self.queued_messages.get() instead of looping through connections
- Since the start() method will hang until a new message is recieved, the bot will now put StopIteration into self.queued_messages after bot.stop() is called
- Since there's only one queue, messages now have a "conn" key, which contains the BotConnection that they came from.
- Instead of sending StopIteration, the IRC thread will send {"conn": BotConnection, "reconnect": True} (a dict) to signify that it needs to be restarted
- IRCConnection and RecieveThread now have a 'botconn' attribute that is the BotConnection they are associated with. They need to know this in order to send messages to the bot.parsed_messages queue containing the BotConnection object
- main.main now takes parameters (bot, input_params) instead of (bot, conn, input_params) because input_params has a conn value in it.