When country was converted to a submodule (by me) the production
installation target was hacked onto the kernel subdirectory Makefile
which wasn't ideal. Introduce a production target into the country
Makefile that does the installation. Since we want the submodule to be
buildable standalone, we can't include the variable definitions from the
upper level, such as $(DIRSEP) and $(CP), so the caller has to pass those
in at build time if using the production target.
Tested on Linux (GCC + Watcom) and DOS (Watcom)
