Replace all references to IUser by UserDelegate in openshift UI

Since we have OpenShift console we have to track if a user has his credentials (especially the pw) filled in or not. User without pw shall not query anything on the PaaS and shall be prompted for a pw when trying to do some backend queries. We therefore created the wrapper UserDelegate. We now should replace all occurrencies of IUser (which is a client library class) by the wrapper UserDelegate.