Set interactive param on oauth provider for reconnect

[dborkan]

This is part of a group of pull requests that add a new "interactive" param to the core.oauth launchAuthFlow API. If this interactive param is false, Chrome + Firefox oauth tabs should open in the background (not be focused). This results in a better reconnect UX for Facebook.

Related pull requests:

• https://github.com/uProxy/uproxy/pull/1698
• https://github.com/freedomjs/freedom/pull/281
• https://github.com/freedomjs/freedom-for-firefox/pull/70
• https://github.com/freedomjs/freedom-for-chrome/pull/78

[salomegeo]

This looks good as long as other freedom cls are submitted in current form :+1: