[MATH-1131] Improve performance of KolmogorovSmirnovTest#kolmogorovSmirnovTest() for large samples. Thanks to Schalk W. Cronjé

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1607864 13f79535-47bb-0310-9956-ffa450edef68