Fixes #87
Fixes #91
Fixes #96
Restored preview functionality.
Merge branch 'feature-star-ratings-and-keywords' into base-design

Conflicts:
	openreview/apps/papers/templates/papers/paper.html
	openreview/apps/papers/templates/papers/review.html
Rewrote starratings

Note: previous version clogged up browser by calling way too many function; couldn't find the culprit so a rewrite was necessary :-(