Fixed generated code when a class extends multiple classes (#38)

* .

* .

* pnp

* ok

* compiles

* ?

* e

* set

* .ToArray()

* n

* ...

* ok

* pnp

* .

* .

* mapster

src-examples/ProxyInterfaceConsumerForPnP/PersonTT.cs

@@ -0,0 +1,15 @@
+namespace ProxyInterfaceConsumer
+{
+    public class PersonTT<T1, T2>
+        where T1 : struct
+        where T2 : class, new()
+    {
+        public T1 TVal1 { get; set; }
+
+        public T2 TVal2 { get; set; }
+
+        public void Call(int x, T1 t1, T2 t2)
+        {
+        }
+    }
+}