BMA /node/summary : dump config's storage

Add storage infos into /node/summary.

New /node/sumary response should be :

{
  "duniter": {
    "software": "duniter",
    "version": "1.8.7",
    "forkWindowSize": 100,
    "storage": {
      "transaction": true,
      "wotwizard": false
    }
  }
}