Remote.WikiExamples: Fix configuration using vtkExternalModuleMacros

This commit fixes error like the following:

```
Requested modules not available:

    WikiExamples
```

The commit lorensen/VTKExamples@3da258b fixes the configuration and build
of VTKWikiExamples as both a VTK remote module and a stand-alone project.
It ensure **first and follow-up configurations** produce similar results
and behave **identically**.

The build was broken following the introduction of
Kitware/VTK@e33b90d (ExternalModule: Improve target export to
allow build against external module).

The commit addresses the issue by introducing the WikiModuleConfig CMake
module responsible for:

* ensuring module information are exported into `VTK_MODULES_DIR` by using
`vtk_module_export_info`.

* using `vtk_module_config` to ensure that variables like `VTK_LIBRARIES`
are set in the current scope when the project is build.

* ensuring required compile definitions (i.e. <module>_AUTOINIT macros
needed for object factory overrides initialization) are used.

Co-authored-by: Bill Lorensen <bill.lorensen@gmail.com>

Remote/WikiExamples.remote.cmake

@@ -6,8 +6,8 @@
 
 # If the environement var WikiExamplesTag exists, use it
 if (NOT DEFINED ENV{WikiExamplesTag})
-  # October 9, 2017 New alternative baselines
-  set(GIT_TAG b73b03bc4bdd7d0053e0c2a5322a94a2bef937d8)
+  # October 21, 2017
+  set(GIT_TAG 3da258b63a92f34f41c01dbed0058435cd6371d5)
 else()
   set(GIT_TAG $ENV{WikiExamplesTag})
 endif()