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
Merge branch 'update_external_module_example-rel' into release

Change-Id: If6d31f4d31afad729c2611c0959d8962f84980d5
Merge branch 'release'

Change-Id: I40b6e785adc4f2062dd64333b89e5c4f70035773
Ensure module files are generated in the build tree

The ExternalMoleculeMacros should ensure that the module data files are
generated in the build tree of the external module, rather than
polluting the VTK tree they are building against. This relies on the
vtkModuleAPI using CMAKE_MODULE_PATH for the original module files.

Change-Id: If134458e014d29f2cd432e2f9248b5c13b50c96b
Merge topic 'external-modules' into master

b5bc9853 Ensure module files are generated in the build tree
Merge branch 'external-modules-rel' into release

Change-Id: I8f5dcabc7a9c6aaef26e897e337b23d0ee1fa9f2
Merge branch 'release'

Change-Id: I0ffa81dd530552a24f91fea493ba821016fde6d8