Add version size (in bytes for wikitext) object to the version object so data consumers can feed it to machine learning model or create some kind of heuristic to determine version quality.

Notes:

• we can just convert wikitext to bytes and get the length of that slice

Schema:

{
  "name":  "Earth",
  "version": {
    "size": {
      "unit_text": "B",
      "value": 100
    }
  },
  // ...other stuff goes here...
}