- better MySQL support
- fix unit tests for other databases than PostgreSQL (MySQL and SQLite
  fail at test_changeset.test_fk(..))

- better SQL scripts support (testing, source viewing)

make_update_script_for_model:
- calculated differences between models are actually differences between metas
- columns are not compared?
- even if two "models" are equal, it doesn't yield so


- refactor test_shell to test_api and use TestScript for cmd line testing
- controlledschema.drop() drops whole migrate table, maybe there are some other repositories bound to it!