Merged requested to merge alanc/libxpresent:config into master
AC_PROG_LIBTOOL was replaced by
LT_INIT in libtool 2 in 2008,
so it's time to rely on it.
Clears autoconf warnings:
configure.ac:47: warning: The macro `AC_PROG_LIBTOOL' is obsolete. configure.ac:47: You should run autoupdate. m4/libtool.m4:100: AC_PROG_LIBTOOL is expanded from... configure.ac:47: the top level
Signed-off-by: Alan Coopersmith firstname.lastname@example.org