Add method SymbolInfoSession()

MtApi/Requests/RequestType.cs

@@ -11,6 +11,7 @@
         OrderDelete     = 6,
         OrderModify     = 7,
         iCustom         = 8,
-        CopyRates       = 9
+        CopyRates       = 9,
+        Session         = 10,
     }
 }

MtApi/Requests/SessionRequest.cs

@@ -0,0 +1,17 @@
+using System;
+
+namespace MtApi.Requests
+{
+    public class SessionRequest : RequestBase
+    {
+        public string Symbol { get; set; }
+        public DayOfWeek DayOfWeek { get; set; }
+        public int SessionIndex { get; set; }
+        public SessionType SessionType { get; set; }
+
+        public override RequestType RequestType
+        {
+            get { return RequestType.Session; }
+        }
+    }
+}