title: Draw rotated rectangle
body: <p>I'm new to C# and .net, just trying to work out how to do something that I thought would be relatively simple. 
  I'm creating a bitmap to be later saved as an image to disk, part of it I want to draw a rectangle shape. 
  I can do this, however I'm looking for a simple way to do this on an angle. I need to be able to specify an angle to draw the rectangle at, I also need to be able to to specify the rotation point (I need to rotate around the top left hand point of the rectangle). </p>
  
  <p>How is this usually achieved with  c#/.net, is there something built in for this sort of thing that I haven't found ?</p>