Add API fields for review request counters and add new query args.

Review Request #5284 — Created Jan. 20, 2014 and submitted — Latest diff uploaded

Information

Review Board
master

Reviewers

The Review Request resource now provides fields for ship_it_count,
issue_open_count, issue_dropped_count, and issue_resolved_count.

Callers can filter these for exact matches by passing, say,
?ship-it-count=. It can also filter through ranges by
appending _lt, _lte, _gt, or _gte on the query parameter.
The results will be filtered accordingly.

Unit tests pass.

Tested various ranges with review requests, and made sure that it
always gave me what I expected.

Tested for off-by-one errors manually and through unit tests.