Work with vNext Meteor auth

I patched _endOfLoginResponse to append the credentialToken and credentialSecret to the url hash. The latest version of meteor needs both of these to work.

This method works even if the meteor app is using the browser-policy package which prevents inline scripts from being executed. But it will only work once the next version of meteor is released (when _endOfLoginResponse is exposed).

More context here: https://groups.google.com/forum/#!topic/meteor-core/Ma3XTZk4Kqg and in issue #3