BUG #14452: Fixed animation in pvbatch.

Animation scene didn't have the time-track setup by default in pvbatch/pvpython.
This was causing GoToLast/GoToFirst not work correctly in pvbatch/pvpython.
Fixed that.

Change-Id: Ibdb7b69421a4c540d64c688fa9e6fe016c627218
Merge topic '0014452_fix_animation_in_python' into next

b8f9e76 BUG #14452: Fixed animation in pvbatch.