getServerOffset = function getServerOffset(server, cb) {
	if (server === true) {
		serverDate(function (date) {
			cb(date.getTime() - now$1().getTime());
		});
		return;
	}
	if (typeof server === 'string') {
		setTimeout(function () {
			cb(dateFromISO(server).getTime() - now$1().getTime());
		}, 0);
		return;
	}
	setTimeout(function () {
		cb(0);
	}, 0);
}
Returns the server offset based on the type of value
will subtract current time from server time resulting in a correction offset
@param server
@param cb
@returns {*}