[plt-scheme] docs.plt-scheme.org

I've changed things so http://docs.plt-scheme.org/ shows the
documentation for the recently released version (currently 4.2).
Having it show the nightly build documentation was a reasonable choice
while the documentation was not still stable.  This involved a DNS
change so it will take a while to propagate through.

The nightly build documentation is still available at
http://pre.plt-scheme.org/docs/html/

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!