More friendly for visual inspector

Added option to disable the statistics portion of the program (which
avoids waiting for any user input, thus allowing benchmarking to occur
without any intervention). Modified the random matrix generator
slightly to avoid near-zero numbers (which could result in division by
zero). Fixed a long unnoticed bug where the match percentage was always
100 or 0 due to improper float conversion. Fixed a bug in GPU kernel 15
caused a few days ago when the wrong kernel was "optimized".