Fix Python module.

Change-Id: Idcd1b30690e0c37073165f085ba9d19031ed4277
Merge topic '14673_fix_follow_data' into next

178c46d8 Fix Python module.
Creating a new module to consolidate animation related classes.

Creating a new module, vtkPVAnimation, to consolidate all classes
related to animation in ParaView into a single module. This makes the
core/rendering modules a little leaner.

Also fixed module dependencies by making several of them
private dependencies.

Change-Id: I9059875d2d37c979d3f7420e3966eb57594dfec9
BUG #14673: Fix follow data.

Follow-data bug arose becase the "reset-camera" would happen before the
scene had updated the views, which is where correct time is passed to
the view.

In order to fix follow-data, we needed to add structure to when cues get
added. To make that possible, we merged vtkPVAnimationScene and
vtkSMAnimationScene since the two don't need to be separate anymore and
cleaned up the "Tick" logic to add this order specific update of cues.

Currently, I am doing that based on the type of the cue. Eventually, we
can add support for "priorities" or something like that it make it more
extensible.

Change-Id: If5c77b43b7b1b56d78e279d6a25cf0f0d39500a8
Merge topic '14673_fix_follow_data' into next

8d62ca27 BUG #14673: Fix follow data.
427fab41 Creating a new module to consolidate animation related classes.