way, we can safely add them to all the document source files in the
repository without changing the INSTALL document output. Long term we
are going to have to decide on a better document generation mechanism
-- this one is really on its last legs and too ad hoc for words.
version number from /sys/conf/osrelease.sh.
replace MACHINE symbol with _MACH, and define _VER for version number.
fileset names must still be updated by hand; this is a bit harder to
fix unless GNU cpp's -traditional-cpp flag is used.
