Switch default database to pg

This is mostly cleaning up a configuration oversight and some work on my local machine.

## Highlights
- Pulled out the default SQLite cruft
- Got a working config/database.yml set up locally
- Removed database.yml from version control for security reasons
- Bumped the ruby version **down** to 2.0.0
- Ran migrations

Note: The only reason I bumped Ruby down was because I've got a machine that's having problems compiling 2.1.1. Since all the gems run great at 2.0.0 and 2.1.1 isn't even a stable release yet, I don't anticipate problems.

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