Update 9.9.2013:1216

reflect_loss_rayleigh.cc/.h		Altered reflection equation to by factoring out a Zb*Zw
								from the numerator and denominator. By doing so we remove chances
								of dividing by zero. In order to make this same information valid
								for shear instances, it required the introduction of a new variable
								(bool) which determines how to calculate the impendence. This also
								required the treating the new Zb in a special way.