Since build-aux/ now contains a number of files previously at the top level, we ignore build-aux/. Therefore, it's not necessary to list any files that are now kept in it. Also, explicitly mark m4/ as a directory to ignore.
Since build-aux/ now contains a number of files previously at the top level, we ignore build-aux/. Therefore, it's not necessary to list any files that are now kept in it. Also, explicitly mark m4/ as a directory to ignore.