Reboot the system

    delay : int
        Optional wait time in seconds before the system will be rebooted.
    message : string
        Optional message to broadcast before rebooting.

    CLI Example:

    .. code-block:: bash

        salt '*' system.reboot
        salt '*' system.reboot 60 "=== system upgraded ==="

def reboot(delay=0, message=None):
    '''
    Reboot the system

    delay : int
        Optional wait time in seconds before the system will be rebooted.
    message : string
        Optional message to broadcast before rebooting.

    CLI Example:

    .. code-block:: bash

        salt '*' system.reboot
        salt '*' system.reboot 60 "=== system upgraded ==="
    '''
    cmd = ['shutdown', '-i', '6', '-g', delay, '-y']
    if message:
        cmd.append(message)
    ret = __salt__['cmd.run'](cmd, python_shell=False)
    return ret