Add instructions for *any* missing command in collect-binaries

missing() {

	[[ $? -eq 127 ]] || return 0

	opt_builtin() {

		echo "Please ensure '$1' from the coreutils package is installed, or"

		echo "the optional Bash builtins are installed and '$1' is enabled:"

		echo "  enable -f <lib-path>/bash/$1 $1"

	} >&2

	case $BASH_COMMAND in

		cp\ *) echo >&2 "Please ensure 'cp' is installed" ;;

		ldd\ *) echo >&2 "Please install the object dependency checker 'ldd'" ;;

		head\ *) opt_builtin head ;;

		ln\ *) opt_builtin ln ;;

		mkdir\ *) opt_builtin mkdir ;;

	esac

}