[US41232](https://rally1.rallydev.com/#/333839219580ud/custom/334203244564?detail=%2Fuserstory%2F482393870060&fdp=true?fdp=true): PDS SDK: Add Term Query Aggregation code example

Example: terms aggregation elasticsearch using Key order

GET /_search
{
  "aggs": {
    "genres": {
      "terms": {
        "field": "genre",
        "order": { "_count": "asc" }
      }
    }
  }
}