Fix typo.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/collections/trunk@1573750 13f79535-47bb-0310-9956-ffa450edef68
Update release information, the next will be 4.1 rather than 4.0.1.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/collections/trunk@1573751 13f79535-47bb-0310-9956-ffa450edef68