public async static Task<Tweet> Tweet(this IUserSession session, string text)
 {
     var parameters = new SortedDictionary<string, string>
                          {
                              {"status", text},
                          };
     var req = session.AuthenticatedPost("statuses/update.json", parameters);
     var response = await req;
     return response.MapTo(Callback);
 }
        public async static Task<Tweet> Retweet(this IUserSession session, Tweet tweet)
        {
            var parameters = new SortedDictionary<string, string>
                                 {
                                     
                                 };
            var path = string.Format("statuses/retweet/{0}.json", tweet.Id);

            var req = session.AuthenticatedPost(path, parameters);
            var response = await req;
            return response.MapTo(Callback);
        }