Add functionality for trophy to be awarded to a user.
The trophy will be associated with the user, review request, and maybe a local site. It will be added to the database, and displayed on the review request page. Also added functionality for a subclass of TrophyType to be registered as a trophy. However, more work is needed to allow for importing trophies via extensions.

All unit tests pass. Checked with review requests 1000, 1001, and 3 and trophies were displayed correctly (or not at all). Also tested with a new database, filled with the fill-database script. Tested with review request ID's 1000, 10000, 1001, 2222, and 3. Appropriate trophies (or none at all) were awarded. The trophies' existence in the database was manually confirmed.