JUDDI-636 adding a subscription callback API, configuration settings to match (Java only)
JUDDI-637 adding some additional documentation
JUDDI-605 functionality stubbed out, however technical implementation is highly dependent on soap stack.

git-svn-id: https://svn.apache.org/repos/asf/juddi/trunk@1516675 13f79535-47bb-0310-9956-ffa450edef68