Added new TasksController#collect_response AJAX endpoint to collect user
response form data as AJAX form submit - this is for when user clicks
'Ready to continue' but we need to wait for timer to expire.
User data change event is now logged as 'key=value' rather than 'key,value'.
cleaned up formatting/whitespace in chat partial
Form managed by tasks_controller now has id='main'.  continue_button.js
logic fixed so that pressing "Go on" button on the main form does an
AJAX form submission, whereas actual form submit event submits the form.
verify form data correctly serialized
bug fix: timer should never display less than 0 minutes or seconds
added interstitial helper