fix and restore example of external module

Install more cmake infrastructure to build external modules
from install tree.
Update vtkLocal example to modular VTK mechanics.
Note:
  wrapped modules still have problems

Change-Id: I2a46fc2f3ec32e05c986fa4cc92f3ad35ee7c12a
Merge topic 'update_external_module_example' into master

bc51f8e3 fix and restore example of external module