feat: new login experience (#2139)

* feat: multiple auth instances

* fix: auth setup + strategy initialization

* feat: admin auth - add strategy

* feat: redirect on login - group setting

* feat: oauth2 generic - props definitions

* feat: new login UI (wip)

* feat: new login UI (wip)

* feat: admin security login settings

* feat: tabset editor indicators + print view improvements

* fix: code styling

client/index-app.js

@@ -14,6 +14,8 @@ switch (window.document.documentElement.lang) {
     break
 }
 
+require('modernizr')
+
 require('./scss/app.scss')
 import(/* webpackChunkName: "theme" */ './themes/' + siteConfig.theme + '/scss/app.scss')