Ping the server, returns False on connection errors

    CLI Example:

    .. code-block:: bash

        salt '*' redis.ping

def ping(host=None, port=None, db=None, password=None):
    '''
    Ping the server, returns False on connection errors

    CLI Example:

    .. code-block:: bash

        salt '*' redis.ping
    '''
    server = _connect(host, port, db, password)
    try:
        return server.ping()
    except redis.ConnectionError:
        return False