Feature evaluations enhancements

I've squashed three relatively minor issues into this feature branch. This includes adding in a new constraint requiring that evaluation form titles are unique to each author of the form, the addition of a "category description" field which allows one of the individual question/category rows in a rubric to be described outside of the individual criteria associated with one of the actual responses, and the addition of a visual indicator to show who the person being evaluated is on the evaluation attempt page through the use of an api call which duplicates the functionality used to populate the people search page results, so privacy levels are taken into consideration, as well as the photos that exist for the user.