TODO

2017.08.04:
v Return a possible error result from plugin action
- Integrate chat
    v IRC plugin
    - Slack plugin
    - Generic chat interface for both IRC and Slack
v Command for the GitHub plugin `git remote set origin URL`
- Hello plugin with random display of greetings


2017.08.15:
v Handle Nothing from `matchPlugin message`
v Handle "sorbot: " prefix
v Use `Data.Text` instead of `String`


2017.08.16:
GitRemoteSetOrigin:
v Figure out how to use capture groups
v UPSERT instead of INSERT


2017.08.17:
v Help plugin
v Way for plugins to only respond over QUERY (like help)
v Add "command" and "description" fields to `Plugin` for use by Help
x Plugin config for whether or not it requires the "sorbot: " prefix
v I18n (http://www.yesodweb.com/book/internationalization)


2017.08.20:
v Factorial plugin
- Translate strings
v --language option
- Feed language to functions that need i18n
v Don't prevent IRC flood when sending the help so that it doesn't take a
  second for each line to appear