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.