V0.6

Updating freedom-social-xmpp to freedom v0.6
Includes using the new core.oauth for credentials on Google & Facebook
Re: control stateObj
No at the moment, the stateObj should be treated as an opaque object, which the core.oauth provider uses to keep track in between calls. Once you call initiateOAuth, it generates a stateObj, which is single-use and must be passed into a subsequent launchAuthFlow call.

Re: specifying a redirect_uri
You can specify an array of redirect_uris which you have registered. See 
https://github.com/freedomjs/freedom-social-xmpp/blob/v0.6/src/core/facebook-auth.js#L4
We pass this array into 
https://github.com/freedomjs/freedom-social-xmpp/blob/v0.6/src/core/facebook-auth.js#L31
The stateObj includes a property which tells you which redirect_uri (of the ones you passed in) the platform has the ability to support. (e.g. the core.oauth provider that uses chrome.identity can only deal with redirect uris of the form https://<appid>.chromiumapp.org/*