Add DMP narrative to metadata records

[briri]

We need to add the DMP narrative elements to the DMP JSON record.

Since we are not currently able to cleanly map questions/answers to the few fields within the current RDA Common Metadata Standard for DMPs schema, we will need to add a new dmphub_narrative array to the record.

The format could be something like:

{ 
  "template_title": "Generic DMP",
  "content": [{
    "section": "Data Preservation",
    "order": 1,
    "questions": [
      {
        "text": "Please describe the data and how you will preserve it.",
        "answer": "Lorem Ipsom ...",
        "order": 1
       },
       {
         "text" : "Will you keep a backup?",
         "answer": "Yes"
         "order": 2
        }
      ]
  }]
}

The API should NOT include these narrative elements when returning data for DMPs with private visibility unless the caller is authorized. We should probably also exclude the description (aka abstract) as well in this scenario.

Once aded, we will need to run a script to resend all DMPs