[keycloak-dev] Updated keycloak.js for session state iframe

I've update keycloak.js to now create the session state iframe by default. By default it runs 'checkLoginIframe' every 5 seconds. It also runs checkLoginIframe in updateToken. If the session is logged out clearToken is called, this will delete subject, token, etc and also invoke the onAuthLogout callback (if one is set). The iframe can be disabled with "init({ checkLoginIframe: false })" and the interval can be set with "init({ checkLoginIframeInterval: 10 })". I've also update the js-console and the customer-portal-js examples, and the JS documentation.