Add a wait between replays of the reference exercise

[shreyapandit]

• Right now the reference exercise loops continuously without stopping.

• We should have a way users can catchup and readjust themselves if they fall too much out of sync

• There is an ongoing discussion about adding a couple of seconds of wait between successive replays of the reference exercise.

• The flow would look like:

  1. Play reference Frames
  2. Wait for 5 seconds
  3. Go to 1

This should repeat till they are on that page that records the exercise.

• We need to be very careful here, because when the wait is happening, we shouldn't capture any live frames during that time. This is substantial effort, both for development and testing.