oauth manually using xamarin.auth

xamarinoauth1.cs

				const string placeQuery = "http://api.v3.factual.com/t/places?geo={\"$point\":[38.544401,-121.742229]}";

				using (var client = new HttpClient())
				{
					var header = Xamarin.Auth.OAuth1.GetAuthorizationHeader ("GET", new Uri ("http://api.v3.factual.com/t/places"), new Dictionary<string,string> { {"geo","{\"$point\":[38.544401,-121.742229]}"} }, 
						"key", "secret", string.Empty, string.Empty);
					client.DefaultRequestHeaders.Add("Authorization", header);

					var res = client.GetAsync(placeQuery).Result;
//					res.EnsureSuccessStatusCode();

					var content = await res.Content.ReadAsStringAsync();

					var clen = content.Length;
				}