chore(greenkeeper): Update typedoc-plugin-external-module-name to version 3.1.0.

Closes #76.

Author: greenkeeper[bot]

packages/resolve-cascade/package.json

@@ -51,7 +51,7 @@
     "source-map-support": "^0.5.3",
     "tslint": "^5.1.0",
     "typedoc": "^0.15.0-0",
-    "typedoc-plugin-external-module-name": "^2.0.0",
+    "typedoc-plugin-external-module-name": "^3.1.0",
     "typedoc-plugin-markdown": "^1.1.8",
     "typescript": "~3.4.4"
   },