Version 0.6 -> 0.7

Big changes this time, deserving the creation of this file.

o Changed from Xm to Xaw (with DrawingArea widget; see ACKNOWLEDGEMENTS),
  which involved a lot of necessary (and usually highly cool) changes:

  - Changed from one DrawnButton per square to one DrawingArea per level.
  - Can trap ButtonPress and ButtonRelease much easier, so implemented
    drag-and-drop moving instead of src-dest-ok clicking.
  - Removed the Source and Dest fields in the main window.
  - Reduced size of internal representations of the muster and graphics.

o Now change cursor while move is in progress (I'm working on changing
  the cursor to a pixmap of the piece being moved, but getting Xpm to
  generate monochrome pixmaps is harder than I thought..)

o Removed last message from message-box if it is no longer applicable.

o Got rid of that irritating beep all the time - now it only happens
  on the events which are both "interesting", and need your attention
  (such as your opponent moving).

o Added some measure of machine configuration and autodetection.

o Fixed an undo bug, a bug with kings and checking them, and one or two
  others.
