Bugfix #117: API Event tags

Add API for tags so events can get the related field.

webapp/urls.py

@@ -19,7 +19,7 @@ from webapp.views import about_view
 # from webapp.views import contact_view
 
 from webapp.views import EventViewSet, SignupFormViewSet, SignupViewSet,\
-    FeedViewSet, ContactsViewSet, SavedQuestionsViewSet, RootView
+    FeedViewSet, ContactsViewSet, SavedQuestionsViewSet, RootView, TagsViewSet
 
 
 class APIRouter(routers.DefaultRouter):
@@ -33,6 +33,7 @@ router.register(r'signup', SignupViewSet)
 router.register(r'feed', FeedViewSet)
 router.register(r'contacts', ContactsViewSet)
 router.register(r'questions', SavedQuestionsViewSet)
+router.register(r'tags', TagsViewSet)
 
 urlpatterns = [
     url(r'^api/', include(router.urls)),