Add empty oauth2 settings to Sandstorm.

sandstorm-pkgdef.capnp

@@ -245,6 +245,12 @@ const myCommand :Spk.Manifest.Command = (
     (key = "BROWSER_POLICY_ENABLED", value="true"),
     (key = "TRUSTED_URL", value=""),
     (key = "WEBHOOKS_ATTRIBUTES", value=""),
+    (key = "OAUTH2_CLIENT_ID", value=""),
+    (key = "OAUTH2_SECRET", value=""),
+    (key = "OAUTH2_SERVER_URL", value=""),
+    (key = "OAUTH2_AUTH_ENDPOINT", value=""),
+    (key = "OAUTH2_USERINFO_ENDPOINT", value=""),
+    (key = "OAUTH2_TOKEN_ENDPOINT", value=""),
     (key = "SANDSTORM", value = "1"),
     (key = "METEOR_SETTINGS", value = "{\"public\": {\"sandstorm\": true}}")
   ]