ACPI clamshell

Disable suspend on lid close when AC is online:

    button/lid)
        case "$3" in
            close)
                if [ "$(cat /sys/class/power_supply/AC/online)" -ne 1 ]; then
                    # suspend-to-ram
                    logger "LID closed, suspending..."
                    zzz
                fi
                ;;
            open)
                logger "LID opened"
                ;;
            *)  logger "ACPI action undefined (LID): $2";;
        esac
        ;;