+ Abort if any of the autotools fails.
    + Check for libtoolize's real name (can be glibtoolize under OS X).
    + Move ltmain.sh to autotools/ if libtoolize created it in '.'.
    + Call autoconf before autoheader and automake to avoid unnecessary calls
      to automake during the make process.
  * configure.in:
    + Use AM_CONFIG_HEADER instead of AC_CONFIG_HEADERS.
    + Substitute LIBAO_LIBS and LIBDTS_LIBS so that automake does not fail.