autoconf warning cleanup
- configure: Use
LT_INITfrom libtool 2 instead of deprecatedAC_PROG_LIBTOOL - configure: pass
noyywraptoAC_PROG_LEXif using autoconf 2.70 or later
Raises minimum autoconf version from 2.60 to 2.64 for m4_version_prereq
LT_INIT from libtool 2 instead of deprecated AC_PROG_LIBTOOL
noyywrap to AC_PROG_LEX if using autoconf 2.70 or laterRaises minimum autoconf version from 2.60 to 2.64 for m4_version_prereq