Invite the welcome user after registration if configured

This will shift focus to the welcome user DM.

We probably don't want to do this for teams, but I shall leave that for another PR that fixes teams WRT to new-guest-access.

Author: Luke Barnard

src/components/structures/MatrixChat.js

@@ -768,8 +768,12 @@ module.exports = React.createClass({
             this._teamToken = teamToken;
             dis.dispatch({action: 'view_home_page'});
         } else if (this._is_registered) {
+            if (this.props.config.welcomeUserId) {
+                createRoom({dmUserId: this.props.config.welcomeUserId});
+                return;
+            }
             // The user has just logged in after registering
-            dis.dispatch({action: 'view_user_settings'});
+            dis.dispatch({action: 'view_room_directory'});
         } else {
             this._showScreenAfterLogin();
         }