feat(doc): add interfaces for documentation purpose
feat(doc): add interfaces for documentation purpose

compodoc/compodoc-demo-todomvc-angular,compodoc/compodoc-demo-todomvc-angular2,compodoc/compodoc-demo-todomvc-angular,compodoc/compodoc-demo-todomvc-angular2,compodoc/compodoc-demo-todomvc-angular2