for consistency's sake, if you update something in the run clustering function also update it in the rerun clustering

Conflicts:
	controllers/answer.py
	models/review.py
	static/css/style.css
	static/js/jquery.countdown.js

Conflicts:
	static/js/jquery.countdown.js
	templates/showanswers.html

Conflicts:
	controllers/answer.py

Conflicts:
	flaskapplication.py
	models/user.py
	static/js/jquery.countdown.js
	static/js/student.js
	templates/_menu_instructor.html
	templates/answerfilter_by_questionid.html
	templates/showanswers.html

made review_stat give a message in stead of a stacktrace if it is called without answers for the question