[RFC] Update to current automake/autoconf/libtool versions.

[DJ Delorie]

IANAL, but...

>  I don't understand -- AFAIK, the GNU GPL doesn't enforce everyone
> making use of files generated by autoconf/automake/gettext/libtool
> to distribute sources of the said tools.

The preferred form for making modifications to configure is to edit
configure.in.  Autoconf is not usually a standard part of the
operating system (esp when we require specific versions).  Therefore,
it is a script used to control compilation, and must be considered
part of the source.

The only exception is that autoconf itself disclaims this connection,
and explicitly allows you to distribute configure without distributing
autoconf itself.  I didn't check the other tools.  I guess we're safe
legally.

We still have the problem of needing a specific version of the tools,
though.

> As I understand, only if binutils use modified tools, the relevant
> sources need to be made available.

There's nothing in the GPL that even mentions patches.