Added SharedTickerType for defining time used for ticker calculations by the API

CryptoExchange.Net/SharedApis/Enums/SharedTickerType.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace CryptoExchange.Net.SharedApis.Enums
+{
+    /// <summary>
+    /// Type of ticker
+    /// </summary>
+    public enum SharedTickerType
+    {
+        /// <summary>
+        /// The ticker data is calculated based on the last 24 hours
+        /// </summary>
+        Day24H,
+        /// <summary>
+        /// The ticker data is calculated based on the start of the day at 00:00 on UTC+0 
+        /// </summary>
+        DayUTc0,
+        /// <summary>
+        /// Ticker data is calculated in a different way or not consistent
+        /// </summary>
+        Other
+    }
+}