Yet another attempt at a fix for bug #35:
- c.initObjects sets c.hiddenRootNode.fileIndex = 'hidden-root-vnode-gnx'
- Added disabled tracing in fc.setMaxNodeIndex. This tracing confirms that caching does not  prevent this method from being called.

@SegundoBob: If this does not solve the problem, please enable tracing in fc.setMaxNodeIndex and report results.

Added a unit test that assert that the gnx of the hidden root node remains unchanged at the time of the test.

Leo build: 20141016103206