Implement OpenID Connect session tracking iframes

[madumlao]

This PR adds openid connect session tracking iframes to oxTrust.

It depends on the opiframe in oxauth working, so it should run on any Gluu with oxAuth#298 resolved. It depends on the same cryptoJS version that oxAuth uses.

The session tracking iframes call /identity/authentication/finishlogout (oxTrust's local logout) when session state is changed, so user has to click "sign in again" to reauthenticate.

[nynymike]

Thanks Mark. We'll have to take some time to process this. But it looks like some nice work.

[willow9886]

@yurem or @shekhar16 can you review this PR?