Hackathon changes on 07/19/2014

Add function  getPropertiesValueOrDefault() in the GUIproperties.java file,
Rework and fix function getPropertiesValueAsList() in the GUIproperties.java file,
Unit test GUIproperties.java and GUIHierarchyConcatenationProperties.java file.
The parameters should have comments that identify what test(s) use them and how they are being used.