* automake.in (@config_aux_path, $config_aux_dir): Rename as ...

* automake.in (@config_aux_path, $config_aux_dir): Rename as ...
($config_aux_dir, $am_config_aux_dir): ... these.
($config_aux_dir_set_in_configure_in): Rename as ...
($config_aux_dir_set_in_configure_ac): ... this.
(%require_file_found): Rename as ...
(%required_file_not_found): ... this.
(handle_languages, handle_texinfo_helper, handle_dist,
handle_configure, handle_emacs_lisp, handle_python,
scan_autoconf_traces, yacc_lex_finish_helper): Adjust to new names.
(scan_autoconf_traces): Call locate_aux_dir.
(locate_aux_dir): New function.
(@require_file_paths): Remove, not used anymore.
(require_file_internal): Look files in only one directory (instead
of @require_file_internal) passed in argument.
(require_file, require_conf_file): Pass the destination directory
to require_file_internal.