Added UTC converter, added UTC DateTimeZoneHandling

CryptoExchange.Net/Converters/UTCDateTimeConverter.cs

@@ -0,0 +1,26 @@
+using System;
+using Newtonsoft.Json;
+
+namespace CryptoExchange.Net.Converters
+{
+    public class UTCDateTimeConverter: JsonConverter
+    {
+        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+        {
+            writer.WriteValue(JsonConvert.SerializeObject(value));
+        }
+
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+        {
+            if (reader.Value == null)
+                return null;
+
+            return DateTime.SpecifyKind((DateTime)reader.Value, DateTimeKind.Utc);
+        }
+
+        public override bool CanConvert(Type objectType)
+        {
+            return objectType == typeof(DateTime) || objectType == typeof(DateTime?);
+        }
+    }
+}

CryptoExchange.Net/ExchangeClient.cs

@@ -24,6 +24,11 @@ namespace CryptoExchange.Net
 
         protected AuthenticationProvider authProvider;
         private List<IRateLimiter> rateLimiters;
+
+        private static JsonSerializer serializer = JsonSerializer.Create(new JsonSerializerSettings()
+        {
+            DateTimeZoneHandling = DateTimeZoneHandling.Utc
+        });
         
         protected ExchangeClient(ExchangeOptions exchangeOptions, AuthenticationProvider authenticationProvider)
         {
@@ -208,7 +213,7 @@ namespace CryptoExchange.Net
                     }
                 }
 
-                return new CallResult<T>(obj.ToObject<T>(), null);
+                return new CallResult<T>(obj.ToObject<T>(serializer), null);
             }
             catch (JsonReaderException jre)
             {