Begin autotools sanitization sequence by requiring ports to explicitly
specify which version of {libtool,autoconf,automake} they need, erasing
the concept of a "system default".
For ports-in-waiting:
USE_LIBTOOL=YES -> USE_LIBTOOL_VER=13
USE_AUTOCONF=YES -> USE_AUTOCONF_VER=213
USE_AUTOMAKE=YES -> USE_AUTOMAKE_VER=14
Ports attempting to use the old style system after June 1st 2004 will be
sorely disappointed.
It is compatible with SGI and TGS Open Inventor, and the API is
based on the API of the InventorXt GUI component toolkit.
PR: 49072
Submitted by: Roland Jesse <roland.jesse@gmx.net>
