support for .NET framework 3.5

Still have bugs

Net35/HandyControl_Net35/Shell/Standard/BITMAPINFOHEADER.cs

@@ -0,0 +1,22 @@
+namespace Standard
+{
+    using System;
+    using System.Runtime.InteropServices;
+
+    [StructLayout(LayoutKind.Sequential, Pack=2)]
+    internal struct BITMAPINFOHEADER
+    {
+        public int biSize;
+        public int biWidth;
+        public int biHeight;
+        public short biPlanes;
+        public short biBitCount;
+        public Standard.BI biCompression;
+        public int biSizeImage;
+        public int biXPelsPerMeter;
+        public int biYPelsPerMeter;
+        public int biClrUsed;
+        public int biClrImportant;
+    }
+}
+