output =
ComputeGammaWeib(x,input)
Compute gamma table using Weibull function.
10/3/93 dhb Created from code written by jms.
10/3/93 dhb,jms Normalize output to max of 1.
Better be sure that last value is max setting.
Psychtoolbox/PsychGamma/ComputeGammaWeib.m