Update RB.Review to use the new API.

Review Request #1970 — Created Dec. 4, 2010 and submitted

Information

Review Board
master

Reviewers

Update RB.Review to use the new API.

This introduces a ready() function to RB.Review, much like
RB.ReviewRequest's. It also provides a ensureCreated() function, which
works like ready() but guarantees an active review that other objects can
then start writing to.