? - Screen help
	/ - Status line help
	e - Plot in residual error mode
	f - Plot in fit to the data mode
	o - Change order of fit
	l - Change lower rejection sigma
	u - Change upper rejection sigma
	r - Reset fit to include rejected pixels
	s - Change upper and lower sigmas to same value
	i - Iterate again
	n - Iterate N times
	q - Quit and accept current solution
	I - Interrupt task immediately