public async Task <JsonResult> RetrieveScores(string centerKey, int offset, int numScores)
{
var retrievalDetails = new RetrieveScoresDetails
{
CenterKey = centerKey,
Offset = offset,
NumScores = numScores
};
var leaderboard = await _leaderboardRepo.RetrieveScoresAsync(retrievalDetails);
return(Json(leaderboard));
}