Normalize URL's to /event/github and /event/travis

This should be the final URL scheme for the time being.  I'm going to
continue to refactor the Sinatra application though.

I'm intentionally committing without updating the tests to see just how
bad it is...
Add example JSON hook when Travis builds fail

This patch adds an example of the JSON that's posted when a Travis build
fails.  This enables behavior testing.
Update dependencies for pry
Add logging for previous URL endpoints

This patch adds more robust logging to the Web application.  We now log
when we discard github events.
Update README with Authentication information

Without this patch there are no instructions of how to configure the end
to end authentication between Github, Travis and Gepetto Bot.

The same authentication token must be used in Github, this is the token
that will be used to identify the message from Travis to PDC.
Add Authentication: SUCCESS logging for Github

This patch just logs successful authentications.
Add staging app URL to Travis notification hooks

This patch configures Travis to notify our staging application as well
as our production application.
Merge branch 'refactor/master/normalize_urls'

* refactor/master/normalize_urls:
  Add staging app URL to Travis notification hooks
  Add Authentication: SUCCESS logging for Github
  Update README with Authentication information
  Add logging for previous URL endpoints
  Update dependencies for pry
  Add example JSON hook when Travis builds fail
  Normalize URL's to /event/github and /event/travis