Adding Beep Boop multi-team support and fixing a few error cases

[selfcontained]

I added the ability to run this bot as a multi-team bot on Beep Boop by wiring in the beepboop-botkit module. As a multi-team bot it allows you to make it public and easy for anyone to add directly to their team via an "Add to Slack" button. More details on what's happening with the beepboop-botkit module can be found here, but in essence, instead of expecting a SLACK_TOKEN when the bot starts up, it receives messages over a socket connection to a Beep Boop service when teams add/remove the bot. This allows your single bot process to handle many teams, and also allows Beep Boop to scale your bot to multiple processes if needed.

I left in the ability to run in single team mode as that's sometimes useful for development, or in case others that fork this want that functionality.

• Also fixed a few error cases I found as I tried some addresses that don't return results.
• Added support for direct messages to the bot