Resources leaks, refactoring and testing

Removing resource leaks from UsageSanityChecker and
refactoring it (encapsulation, removal of copy and paste, constants...)

Modularize static method for closing Statments in TransactionLegacy
and reusing this new method from other classes (Upgrade2214to30)

Create Unit and Integration Tests for UsageSanityChecker

Add DBUnit cases and integration profile for nitegration tests as
a base for future DB tests