title: How to Create a Gdiplus::Bitmap from an HBITMAP, retaining the alpha channel information?
body: <p>When I create a new Gdiplus::Bitmap using the Bitmap::FromHBITMAP function,
  the resulting Bitmap is opaque - none of the partial transparency from the original HBITMAP is preserved.</p>
  
  <p>Is there a way to create a Gdiplus::Bitmap from an HBITMAP which brings across the alpha channel data?</p>