New objects, but the whole design of the DB is broken.

That is, its untestable.
Refactored to get a Databaser object.

Refactor to let DB objects hold an instance of their DB connection, such
that I can create DB out of nowhere for testing purpose and delete the
DB right away.
Partial test, with red for PG support.
SQLite and PGres work for connection.  Need more tests.
More tests.
FindPostById works for SQLite but not PG
Add test for Destroy.  Still PG is broken.
Complete test set.  SQLite passes all, not PG.
Merge pull request #1 from aybabtme/refactor_db

Deep refactor db package, for better testability and portability to different DB.