nextSunAction (date = moment()) {
		return date.isBetween(this.sunrise, this.sunset) ? "sunset" : "sunrise";
	}
Determines if the sun sets or rises next. Uses the current time and not
the date from the weather-forecast.
@param {Moment} date an optional date where you want to get the next
action for. Useful only in tests, defaults to the current time.
@returns {string} "sunset" or "sunrise"