private HttpWebRequest CreateWebApiRequest(String relativeUri)
{
var request = (HttpWebRequest)WebRequest.Create(new Uri(_uri, relativeUri));
request.ContentType = SchedulerConstants.RequestJsonContentType;
request.Headers.Add("Authorization",
new Signature(this._subscriptionId, this._secretKey).ToString());
HttpRequestCachePolicy noCachePolicy = new HttpRequestCachePolicy(HttpRequestCacheLevel.NoCacheNoStore);
request.CachePolicy = noCachePolicy;
return request;
}