* libtool.m4 (_AC_PROG_LIBTOOL): Run before AC_LIBTOOL_GCJ.

* libtool.m4 (_AC_PROG_LIBTOOL): Run before AC_LIBTOOL_GCJ.
Add ltcf-c.sh to LIBTOOL_DEPS.  Run AC_LIBTOOL_CXX and
AC_LIBTOOL_GCJ on demand.
(AC_PROVIDE_IFELSE): Define for non-CVS autoconf compatibility.
(AC_LIBTOOL_CXX): Accept multiple executions.  Add ltcf-cxx.sh
to LIBTOOL_DEPS.  Reset config.log output.
(AC_LIBTOOL_GCJ): New macro.
* libtoolize.in: Copy ltcf-cxx.sh if AC_PROG_CXX is found.
Copy ltcf-gcj.sh when appropriate.
* doc/libtool.texi (AC_LIBTOOL_CXX): Doesn't have to be
explicitly called.
(AC_LIBTOOL_GCJ): Document.
* tagdemo/configure.in (AC_LIBTOOL_CXX): Don't call.