CoreAstroAlgs - CASHalfFluxDiameter:  alg now uses scaled values for both distances and brightness values. All distances are now scaled by the largest of {pixel width, pixel height} and pixel brightness values are scaled by the average image brightness, in order to work with numbers that aren't significantly larger than 1. Also decreased the tolerances for both the radius and the brightness goal.
Merge branch 'master' of https://github.com/simonct/CoreAstro