LANG-922 - Add isOneTrue(booleans...) to BooleanUtils to preserve old behavior of BooleanUtils.xor(booleans...). Added isOneTrue for primitives and wrappers, isOneFalse still missing.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@1532491 13f79535-47bb-0310-9956-ffa450edef68