Having some trouble with the starter app. I've done some local modifications, but whenever I restart the app with 'gulp serve', it crashes when trying to load the Common-module. If I remove one of the submodules (i.e. Navbar) from the common module, it runs OK. If I add the submodule back in, it also runs OK. At this stage, the code is exactly the same as when I ran it the first time. This is done when gulp serve is running and is continuosly building the app. If I restart the process, the same problem reoccurs. Has anyone seen this problem before and know how to fix it?