////////////////////////////////////////////////////////////////////////////////
/// @startDocuBlock JSA_get_api_collection_count
/// @brief Counts the documents in a collection
///
/// @RESTHEADER{GET /_api/collection/{collection-name}/count, Return number of documents in a collection}
///
/// @RESTURLPARAMETERS
///
/// @RESTURLPARAM{collection-name,string,required}
/// The name of the collection.
///
/// @RESTDESCRIPTION
/// In addition to the above, the result also contains the number of documents.
/// **Note** that this will always load the collection into memory.
///
/// - *count*: The number of documents inside the collection.
///
/// @RESTRETURNCODES
///
/// @RESTRETURNCODE{400}
/// If the *collection-name* is missing, then a *HTTP 400* is
/// returned.
///
/// @RESTRETURNCODE{404}
/// If the *collection-name* is unknown, then a *HTTP 404*
/// is returned.
///
/// @EXAMPLES
///
/// Requesting the number of documents:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCollectionGetCollectionCount}
///     var cn = "products";
///     db._drop(cn);
///     var coll = db._create(cn, { waitForSync: true });
///     for(var i=0;i<100;i++) {
///        coll.save({"count" :  i });
///     }
///     var url = "/_api/collection/"+ coll.name() + "/count";
///
///     var response = logCurlRequest('GET', url);
///
///     assert(response.code === 200);
///
///     logJsonResponse(response);
///     db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
/// @endDocuBlock
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