Add feature for event logging during recording

[nicoleprovenza]

This is a "nice-to-have", non-urgent new feature that would enable the participant to submit notes on what they are doing or how they are feeling during a recording.

UI Could look something like:

Symptom/Event Log
Add a note about how you are feeling or what you are doing during this recording.

With a text box for text entry, and a Submit button below.

The event should be saved in the EventLog.json output file