STYLE: Improve readability of EXERCISE_BASIC_MRML_METHODS macro

This commit makes it easier to read through the different test
associated with the macro.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22584 3bd1e089-480b-0410-8dfb-8563597acbee
STYLE: Split MRML Node EncodeString tests into two different tests

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22585 3bd1e089-480b-0410-8dfb-8563597acbee
BUG: Fix vtkMRMLModelHierarchyNodeTest1

Since calling GetID() on a newly instantiated node is expected to
return NULL and that attempting to print a NULL string on windows
results in a crash. The test was failing only on windows.

This commit remove the print statement in the test and also add test
test for GetID and GetNodeTagName to EXERCISE_BASIC_MRML_METHODS so that
the default value for every node is verified.

Since there is already a test printing the value if it fails, also
remove extra debug statement printing the number of children in
the hierarchy node.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22586 3bd1e089-480b-0410-8dfb-8563597acbee