PLT-3633 EE: Add Google and Office365 SSO through OAuth2 (#3660)

* EE: Add Google and Office365 SSO through OAuth2

* Add localization strings

* Text tweaks for PLT-3633

* Added sign-up button for Office 365

* Updated some error messages and a bit of licensing

* Updated sign-in method section in user settings to include Google and Office365

* Added more localization strings

webapp/routes/route_admin_console.jsx

@@ -14,6 +14,7 @@ import PolicySettings from 'components/admin_console/policy_settings.jsx';
 import LogSettings from 'components/admin_console/log_settings.jsx';
 import EmailAuthenticationSettings from 'components/admin_console/email_authentication_settings.jsx';
 import GitLabSettings from 'components/admin_console/gitlab_settings.jsx';
+import OAuthSettings from 'components/admin_console/oauth_settings.jsx';
 import LdapSettings from 'components/admin_console/ldap_settings.jsx';
 import SamlSettings from 'components/admin_console/saml_settings.jsx';
 import SignupSettings from 'components/admin_console/signup_settings.jsx';
@@ -88,6 +89,10 @@ export default (
                 path='gitlab'
                 component={GitLabSettings}
             />
+            <Route
+                path='oauth'
+                component={OAuthSettings}
+            />
             <Route
                 path='ldap'
                 component={LdapSettings}