Create a graphical memory-debugging "minimap"

[hintron]

Have a "minimap" of memory and registers that will graphically show reads and writes. Perhaps have a read, a write, and a read-write minimap. Have it heat-mapped so that more recent accesses are visible as red, the least-recent accesses are green and blue, and untouched accesses are black. Also have separate minimaps for code and data accesses.

[hintron]

I got a graphical display window working (f9ade87), but for now I am content with just displaying the same image that I was able to generate and view in Gimp. The memory minimap idea can be put on the shelf for now.