state of reality: comment out O2 references since 1.6 won't support the
O2, add notes on installing via a net-booted kernel, disk partitioning
(disk must have IRIX volhdr, one-disk split NetBSD/IRIX install has not
been tested and may/may not work). Also expand/add some examples.
XXX: Should add info on the "extra" kernel sets like the INSTALL_INDY,
etc. sets.