The new query tests for the datagrids unveiled a number of excess

queries when working with Local Sites. We were querying one Local Site

per row when viewing any review request datagrid on a Local Site. This

was due to the lack of any select_related or equivalent.
This change fixes that, significantly reducing the overhead and the

removing the padded excess queries in the unit tests.
In the process, I've audited the code, cleaned up some calls to help

avoid potential problems down the road, and reduced additional queries

that involved Local Sites, helping keep queries simpler on a standard

setup.

Unit tests pass.
Tested all the datagrids, making sure there were no apparent regressions.