anchor.diff:  }
   
   Add an MV Metadata Contract
  -POST /lps/{lpID}/mv-md
  -> Authorization: MAC id="...", ts="...", nonce="...", mac="..."
  +POST /lps/{lp-id}/mv-md
  +> Authorization: MAC id="...", ts="...", nonce="...", mac="..."
  +< 201
   {
       "identifying_factors": 
       [
  
positive.code:                 "us-en": "Password"
              }
          },
      ]
  }
  < 201
  {
      "identifying_factors": 
      [
          {
              "fieldKey": "member_first_name",
              "validation": "^[A-Za-z]{3,15}$",
              "name": {
                  "us-en": "First Name"
              }
              "description": {
                  "us-en": "Member's First Name"
              }
          },
          {
              "fieldKey": "member_last_name",
              "validation": "^[A-Za-z]{3,15}$",
              "name": {
                  "us-en": "Last Name"
              }
              "description": {
                  "us-en": "Member's Last Name"
              }
          }
      ],
      "authenticating_factors": 
      [
          {
              "fieldKey": "member_password",
              "validation": "^[A-Za-z]{3,15}$",
              "name": {
                  "us-en": "Password"
              }
              "description": {
                  "us-en": "Password"
              }
          },
      ],
      "links": {
          "self": {
              "href": "https://sandbox.lcp.points.com/lps/{lpID}/mv-md/9876"
          }
      }
  }
  
negative.code:     "balance": 23000,
      "links": {
          "self": {
              "href": "https://sandbox.lcp.points.com/v1/lps/glbl/mvs/123456"
          }
      }
  }
  