Log Message:
Update to 1.5.6 (OK'd by skrll).

* In libtool-base, generate shlibtool with a simple sed script; no full
  build is actually needed.

Changelog:

New in 1.5.6: 2004-04-11; CVS version 1.5.5a, Libtool team:
* Installs libltdl files properly in $prefix/share/libtool/libltdl. 1.5.4
  did not install them at all.
* libltdl correctly guesses the extension for loadable modules again.

New in 1.5.4: 2004-04-03; CVS version 1.5.3a, Libtool team:
* Bug fixes.