* demo/Makefile.am (hc-direct, hc-libpath, hc-minusL): link with

* demo/Makefile.am (hc-direct, hc-libpath, hc-minusL): link with
$$hardcode_libdir_flag_spec, if available, with libdir=$(libdir),
to make sure the hardcode_* variables will produce the expected
results even in the presence of a hardcoding flag; depend on
libhello.la having been installed already
(hc-libflag): link with the installed library, but try to
hard-code the uninstalled one
* doc/libtool.texi: document the changes