Generic Search #102

Implement a generic search service. Its parameters should take simple data arguments pertaining to field value comparisons and simple search logic (AND / OR).

It might make sense to bring in a third-party library to accomplish this. Investigate. The problem space seems non-trivial so prefer to avoid reinventing the wheel here.

Current search implementation is entity-specific (Person), not generalized, and relies on passing filter object references with behavior rather than pure data (java.util.Predicate) which poses challenges for testing and reusability.