TgSharp.TL: fix invalid Context type initialization for TLVector

Fixes #15

Author: knocte

src/TgSharp.TL/ObjectDeserializer.cs

@@ -12,6 +12,7 @@ public class ObjectUtils
         public static object DeserializeObject(BinaryReader reader)
         {
             int Constructor = reader.ReadInt32();
+
             object obj;
             Type t = null;
             try
@@ -21,8 +22,9 @@ public static object DeserializeObject(BinaryReader reader)
             }
             catch (Exception ex)
             {
-                throw new InvalidDataException("Constructor Invalid Or Context.Init Not Called !", ex);
+                throw new InvalidDataException("Invalid constructor, or invalid TLContext static initialization", ex);
             }
+
             if (t.IsSubclassOf(typeof(TLMethod)))
             {
                 ((TLMethod)obj).DeserializeResponse(reader);

src/TgSharp.TL/TLContext.cs

@@ -19,7 +19,19 @@ static TLContext()
                      where t.IsSubclassOf(typeof(TLObject))
                      where t.GetCustomAttribute(typeof(TLObjectAttribute)) != null
                      select t).ToDictionary(x => ((TLObjectAttribute)x.GetCustomAttribute(typeof(TLObjectAttribute))).Constructor, x => x);
-            Types.Add(481674261, typeof(TLVector<>));
+
+
+            var vectorTypeId = 481674261;
+            var genericVectorType = typeof (TLVector<>);
+
+            Type type;
+            if (Types.TryGetValue(vectorTypeId, out type)) {
+                if (type != genericVectorType && type != typeof(TLVector)) {
+                    throw new InvalidOperationException ($"Type {vectorTypeId} should have been a TLVector type but was {type}");
+                }
+            } else {
+                Types [vectorTypeId] = genericVectorType;
+            }
         }
 
         public static Type getType(int Constructor)