More work on ServiceConfigUtil.java - based on a patch from Christoph Neuroth with modifications by me. Client code now uses the new models and the DOM parsing static methods have been removed. The serviceengine.xml file handling is now thread-safe.

https://issues.apache.org/jira/browse/OFBIZ-5204


git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1490112 13f79535-47bb-0310-9956-ffa450edef68