A yesodMiddleware that notifies Bugsnag of exceptions

yesodMiddleware is the only way to handle things as actual exceptions. The alternative, using errorHandler, means you would only ever see an "InternalError Text" value.

The main downside to this middleware is that short-circuit responses also come through the middleware as exceptions, and must be filtered. Unless of course you want to notify Bugsnag of 404s and such.