Add image pause for readjustment

[JMankewitz]

In Active and CoSample, Martin's experiment paused right before the contingent phase to readjust the child and recalibrate if needed. I think I should introduce something similar right after the familiarization and before the active sample test.

Babies settle into a watching position during the familiarization, so I might lose their track.

[JMankewitz]

Still need to test in-lab to ensure audio works during & after recalibration.

[JMankewitz]

Experiment audio is fine, but the attention grabbing audio from tobii studio is killed. We'll see if this still works for squirmy kids.