Fix comment flash

<https://www.pivotaltracker.com/story/show/79135966>

- Litepapers no longer have an unread comment count
- the dashboard counts commentLooks to show unread comments on papers
- when the event-stream receives an updated comment, it reloads just the comment rather than the comments task. There are now fewer repaints/re-renders.

Cheers,
CT ASB DT

Woops, we committed as Chandu instead of ASB.