Sixth edition of the sysinst/Lua diff

The sixth revision of the diff to add Lua scripting capabilities to
sysinst solves the problem of overflowing floppies
(http://en.wikipedia.org/wiki/Floppies) or ramdisk images on certain
ports like e.g. atari or x68k.

distrib/utils/sysinst/Makefile.inc has the variable USE_LUA, which is
set to yes by default.  To disable the inclusion of Lua in a certain
image, add "CRUNCHENV+=  USE_LUA=no" to the respective Makefile (and
don't add "-llua" to the LIBS section of the list file).  Thanks to
Allan Barret (apb@) for this hint.  In the long term, however, a better
solution should be found for "short breathed" ports.

Find the diff at http://www.netbsd.org/~mbalmer/diffs/sysinst_006.diff