Basic Sentry setup

Not running the install script automatically at this point yet.

environments/production.json

@@ -36,6 +36,9 @@
       "alternate_domains": [
         "mastodon.w7nooprauv6yrnhzh2ajpcnj3doinked2aaztlwfyt6u6pva2qdxqhid.onion"
       ]
+    },
+    "sentry": {
+      "allowed_ips": "10.1.1.0/24"
     }
   }
 }