Backport database package enhancements from Framework

This PR is backporting the refactored importers and exporters from the Framework package.  Work was done there to start abstracting out this code to ease in building these classes for the other drivers.  Note the amount of duplicated code removed here.

With the refactored classes, I've also taken the chance to clean up the tests a bit.  The unnecessary inspectors are removed from all database tests in favor of our Reflection helper class, and in some cases, the inspectors were just plain unnecessary.

Lastly, test coverage for the often overlooked `JDatabaseFactory` is added here.