message: use an array instead of object to store articulation spec
diff: "count": 12
  }
  },
  - "articulationSpec": {
  + "articulationSpec": [
  + {
  "leftWrist": {
  "$data": {
  "data": "tracker/0",
  "type": "joint"
  }
  }
  + }
  },
  + {
  "rightWrist": {
  "$data": {
  "data": "tracker/6"
  }
  }
  }
  - },
  + }
  + ],
  "semantic": {
  "hands": {
  "left": {
  }
  }
  },
  - "automaticAliases": {
  - }
  + "automaticAliases": {}
  }
  \ No newline at end of file
  