Turn on off-topic plugin by default

plugins.default.json

@@ -3,11 +3,14 @@
     "coral-plugin-respect",
     "coral-plugin-like",
     "coral-plugin-facebook-auth",
-    "coral-plugin-auth"
+    "coral-plugin-auth",
+    "coral-plugin-offtopic"
   ],
   "client": [
     "coral-plugin-respect",
     "coral-plugin-like",
-    "coral-plugin-auth"
+    "coral-plugin-auth",
+    "coral-plugin-offtopic",
+    "coral-plugin-viewing-options"
   ]
 }