- here, the list-of-integers module (intlist.c and intlist.h) and
  it's test program (testlist.c) have been entirely separated from
  applications (eg. the avgwordlen program) that USE intlists.  In
  other words, this is just the contents of the "lib" directory
  from the previous version, with a modified Makefile.

- The Makefile builds two things:
  	- the executable testlist for us to test that intlist works
	- the library libintlist.a containing intlist.o, using
  	  ar and ranlib.

- now, the Makefile has a new "install" target, to install the library
  in the TOOLDIR/lib/ARCH directory, and intlist.h into TOOLDIR/include.

- look in 06.avgwordlen-only for the avgwordlen program, set to build
  against the intlist library installed in c-tools.
