Update the RB.DiffCommentReply and RB.ReviewReply code for the new API
Review Request #1983 — Created Dec. 7, 2010 and submitted
This updates both the RB.DiffCommentReply and RB.ReviewReply objects to use the new API.
Unit tests pass. Tested replying to existing diff comments and to reviews. Also tested that clearing a draft comment deleted it from the review.