Suggestion for "Wrong FASL version" error

[Henry Lieberman <lieber@media-lab.media.mit.edu>]

When upgrading a large system over a FASL version change, 
it would be helpful if the code that detected a "Wrong FASL Version"
error made this a warning instead of an error and loaded the
.Lisp file instead [as LOAD loads the .lisp if it newer than the .fasl].
This is harmless, and is better than the fatal error because 
loading files may cause others to be loaded via require, etc. and
you'd rather find them all in one pass rather than have to go 
through many loading passes.