SLING-3988- Content Navigator does not show nodes with escaped names

Added some test cases for the JcrContentContentProvider 

- 1 basic test for navigating a nested content structure
- 1 test which demonstrates the problem scenario for this bug, currently
@Ignored

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1628733 13f79535-47bb-0310-9956-ffa450edef68