Change to SAX parser
Change the XML parsing invocation to SAX
Do minor changes in Utils
Adapt the NotifyContextRequest tests to SAX
Adapt other test classes to SAX
Minor changes in TestUtils
Add a Json loader based on a string as a testing utility
Add an unordered Json simple test and use the Json loader utility test
Add test cases regarding unordered, null list of attributes and nested XML and Json documents
Remove the DOM parsing
Merge pull request #221 from telefonicaid/hardening/201

hardening/201