Add a new tab to rooms with state events (#108)

Co-authored-by: Michael Albert <37796947+awesome-michael@users.noreply.github.com>

src/App.js

@@ -71,6 +71,7 @@ const App = () => (
     <Resource name="joined_rooms" />
     <Resource name="pushers" />
     <Resource name="servernotices" />
+    <Resource name="room_state" />
   </Admin>
 );