Support editor input/data definitions in structure.json

[steve2507]

The node editor contents are mostly used to expose input fields to store in the flow, being consumed by the node.data map.
This could be made much simpler for nodepack developers, by simply allowing a similar structure to be added to the structure.json;

{
  "name": "my-node",
  "dataStructure": {
    "my-data-field": {
      "type": "text", // text, textarea, password, select, checkbox, number
      "required": true,
      "placeholder": "my input", // optional
      "label": "some label",  // optional, refer to placeholder || editorData[x]
      "options": [], // only applies to type=select
      "pattern": "$.*?regex" // optional
      "min": 0, // optional, only applies to type=number
      "max": 10, // optional, only applies to type=number
      "minlength": 1, // optional, only applies to type=text, password
      "maxlength": 2 // optional, only applies to type=text, password
    }
  }
}

In the example above, the field value would be accessible in the node through NODE.data['my-data-field']