Add input validation and test cases

Based on the JS303 bean validation work done in AQ-173, add validation and tests to SAPI and/or security component levels to validate user input. Both positive and negative tests for passed parameters (protect against SQL injection or cross site scripting issues, for example). Also validate security policies, such as administrators only being able to access/manipulate users within a realm.

The 3 primary expected outcomes are:

1) Definition and documentation of valid data for SAPI (added to JavaDoc and thereby, the API doc)
2) Increased coverage testing numbers (we should be striving for around 70%)
3) Implementation and validation of security policies.