Configure Renovate (#71)

* chore(deps): add renovate.json

* manage cargo as well

* force cargo as enabled

renovate.json

@@ -0,0 +1,9 @@
+{
+  "extends": [
+    "config:base"
+  ],
+  "enabledManagers": ["cargo", "npm"],
+  "cargo": {
+    "enabled": true
+  }
+}