Optimize vtk

[doutriaux1]

@aashish24 @dlonie @chaosphere2112 @williams13

This is the merge for animations

I still need input to add tests for animations, not sure how to go at it, but just added option to "preserve" png files at exit might be the way to go.

Lots of changes, so it's a big job to review.

[alliepiper]

FWIW, it's generally a bad idea to mix large whitespace-only (or other maintenance-oriented) changes with actual code changes.

It makes it more difficult for reviewers to find the actual changes that need reviewing, and leads to odd VCS histories (for instance, changing non-VTK related files in a topic that is focused on cleaning up VTK usage).

[doutriaux1]

i think these are due to our pre-commit that refuses to have any white space at the end of lines.... VERY annoying, so I believe I ran some sed on the files to get rid of all of them massively