More work on ServiceConfigUtil.java - based on a patch from Christoph Neuroth with modifications by me. The static helper methods now use the models instead of parsing the DOM tree. This commit makes a small API change - the helper methods now throw an exception if there is a problem with the serviceengine.xml file. The original code would just hide the errors, so client code didn't know anything was wrong.

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


git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1490004 13f79535-47bb-0310-9956-ffa450edef68