buildworld update committed

[Matthew Dillon]

    Have at it.  Note that 'make buildworld' will take a lot longer now
    because it actually removes the entire buildworld object tree (previously
    only a portion of the tree was removed), but once you've done a buildworld
    you should be able to get away with just doing 'quickworld' after that
    (at least for a while).

    The new buildworld uses a much nicer, logical directory arrangement
    in /usr/obj/usr/src, amoung other features.

    I have made progress with -j n support but I'm sure there are still
    issues.  If you want to help test, and you get a build failure, it's
    only useful to me if you have the entire make output available for
    download (don't post it since it's going to be large).  e.g.

    xterm1# make -j 4 buildworld >& /tmp/bw.out

    xterm2# tail -f /tmp/bw.out | fgrep ===

    I will continue running tests and almost certainly be making little
    tweaks here and there.  Hopefully I haven't broken anything too badly :-)

						-Matt