Enforce restriction to create new rooms

app/controllers/rooms_controller.rb

@@ -31,6 +31,12 @@ class RoomsController < ApplicationController
       head :forbidden unless Current.user.can_administer?(@room)
     end
 
+    def ensure_eligible_to_create_rooms
+      if Current.account.restrict_room_creation_to_administrators? && !Current.user.administrator?
+        head :forbidden
+      end
+    end
+
     def find_messages
       messages = @room.messages.with_creator.with_attachment_details.with_boosts