GitLab

3 effects in this commit, with the first being the main one:

1. Fix the "`missing' script is too old or missing" warning. See:
   <https://lists.gnu.org/archive/html/automake/2010-08/msg00108.html>

2. By moving AC_CANONICAL_TARGET down in order, we are now able to
   set the directory for auxiliary scripts. For now it's still './'.
   I added the line "AC_CONFIG_AUX_DIR([.])" to show that the directory
   change is possible.

3. AC_USE_SYSTEM_EXTENSIONS includes checks from AC_PROG_CC, by moving
   the former macro down, we can save size in 'configure' by not
   generating repeated checks.