Constrained EmpiricalDistribution sample/getNextValue methods to return
values within the range of the data; correctly linked RandomGenerator to
superclass so that RealDistribution reseedRandomGenerator method works.

JIRA: MATH-984



git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1604639 13f79535-47bb-0310-9956-ffa450edef68
Reuse method from "MathArrays".


git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1604641 13f79535-47bb-0310-9956-ffa450edef68
Unnecessary brackets.


git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1604642 13f79535-47bb-0310-9956-ffa450edef68