message: Set minimum required Boost to 1.47.0
diff: @@ -572,8 +572,11 @@ fi
  if test x$use_boost = xyes; then
  +dnl Minimum required Boost version
  +define(MINIMUM_REQUIRED_BOOST, 1.47.0)
  +
  dnl Check for boost libs
  -AX_BOOST_BASE
  +AX_BOOST_BASE([MINIMUM_REQUIRED_BOOST])
  AX_BOOST_SYSTEM
  AX_BOOST_FILESYSTEM
  AX_BOOST_PROGRAM_OPTIONS
  