code changes from our session

load_detector.,m:
changed texture feature threshold to 0.24 (hard coded!!!)

detection_test.m:
-added timing (tic/toc)
- changed radius range and steps
- changed edges map (union of red & green channel edges)
- using edges map instead of rgb image as hough's input
- hough param: bright polarity only
- saving output from all images in "detection_res.mat"