use AtomicInteger for Limit/Offset state, plus Validate dog food

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/functor/trunk@1539877 13f79535-47bb-0310-9956-ffa450edef68
remove bean constructors for utility classes

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/functor/trunk@1539878 13f79535-47bb-0310-9956-ffa450edef68