document reason for requiring Maven < 3.2.x

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/weaver/trunk@1578236 13f79535-47bb-0310-9956-ffa450edef68
specify that 'main' javadocs are current

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/weaver/trunk@1578237 13f79535-47bb-0310-9956-ffa450edef68