Add an end point to determine if any collections contain products that match specified parameters

[felixMasonJncc]

End Point
POST: /search/collections-containing-products

Query same as /search/products

Result

{
    "query": {...
    },
    "result": [
        {"collection_name" : "collection/name", "count" : "12"}
        ....
    ]
}

Update online docs