ENH: Restore / convert Infovis examples

The infovis examples were never updated to VTK6. This patch restores
those examples and updates them to work with VTK6.

Change-Id: I29354858983c9a1198a0a40a2552e75d7e2ac62a
Signed-off-by: Andrew Maclean <andrew.amaclean@gmail.com>
Merge topic 'RestoreInfovisExamples' into master

0a0ff7af ENH: Restore / convert Infovis examples