New VM and byte-compiler improvements

[Brian Rice]

Hi all,

Lee has refactored the VM design so that delegation slots are stored  
on objects' maps, resulting in roughly a 10% reduction in image  
sizes. The new VM sources and images for working with them are now  
posted to the alpha area - note that the old VM will not run the new  
images.

There is also a byte-compiler improvement so that even fewer code  
blocks will be allocated on the heap, resulting in another  
incremental speed improvement.

I have also removed the post-bootstrap processing of library sources  
for the recent auto-loading feature. I am currently debugging a new  
implementation which builds a quick-and-dirty database that the image  
will read on startup. I'll inform when that's finished.

Enjoy! :)