message: bump rdflib to 0.16.9
diff: "dependencies": {
  "escape-html": "^1.0.3",
  "node-uuid": "^1.4.7",
  - "rdflib": ">=0.16.6",
  + "rdflib": ">=0.16.9",
  "regenerate": "^1.3.2",
  "solid-auth-client": "^1.0.0",
  "solid-auth-tls": "^0.1.2"
  