support for .NET framework 3.5

Still have bugs

Net35/HandyControl_Net35/Shell/Standard/IObjectCollection.cs

@@ -0,0 +1,18 @@
+namespace Standard
+{
+    using System;
+    using System.Runtime.InteropServices;
+
+    [ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("92CA9DCD-5622-4bba-A805-5E9F541BD8C9")]
+    internal interface IObjectCollection : Standard.IObjectArray
+    {
+        uint GetCount();
+        [return: MarshalAs(UnmanagedType.IUnknown)]
+        object GetAt([In] uint uiIndex, [In] ref Guid riid);
+        void AddObject([MarshalAs(UnmanagedType.IUnknown)] object punk);
+        void AddFromArray(Standard.IObjectArray poaSource);
+        void RemoveObjectAt(uint uiIndex);
+        void Clear();
+    }
+}
+