Teach vtk_module_library to add a <module>.HeaderTest test.  Teach
HeaderTesting.py to exclude headers containing a special comment like
those added by the parent commit.

Exclude GUISupport/Qt* and Views/Qt because the modules have headers
that are not expected to follow VTK conventions.  Temporarily exclude
the Chemistry/Core module until its headers are fixed or marked as
excluded (they came from the Chemistry kit in monolithic VTK which had
no header test).

Change-Id: Ib6e1313a866db154f7b0e94aa340a10b16f8b9ca