blockcore-dns api endpoint to fetch indexer ip addresses

[dangershony]

An example of how a json response could look

{
   "ServerLocations": [
      {
         "Location": "1.2.3.4:9010",
         "ProjectType": "Indexer"
      },
      {
         "Location": "1.1.1.1:443",
         "ProjectType": "Indexer"
      },
      {
         "Location": "1.1.1.1:5555",
         "ProjectType": "Vault"
      }
   ]
}