truthy(val, deflt) {
    let ret;
    if (["on", "On", "ON", "true", "True", "TRUE", "1", true, 1].includes(val)) ret = true;
    else if (["off", "Off", "OFF", "false", "False", "FALSE", "0", false, 0].includes(val)) ret = false;
    else ret = deflt;
    return ret;
  }
Returns true/false or a default value for truthy/falsy and other values
@param {string|number|boolean|*} val The value to test
@param {any} deflt Default value to use if the value is not truthy/falsy
@returns {boolean|any} The truth! Or the default