title: Set dimensions for UIImagePickerController "move and scale" cropbox
body: <p>How does the "move and scale screen" determine dimensions for its cropbox?</p>
  
  <p>Basically I would like to set a fixed width and height for the "CropRect" and let the user move and scale his image to fit in to that box as desired.</p>
  
  <p>Does anyone know how to do this? (Or if it is even possible with the UIImagePickerController)</p>
  
  <p>Thanks!</p>