Move `database.php.default` to `database.php`

This move allows developers to setup their applications *much* more quickly. A single clone of the repository should be enough to get the database connected, as opposed to a further command after project creation.

This change is made possible because the `database.php` can now retrieve it's configuration from an environment variable, which makes deployment to many environments much easier.
Move environment helper methods to allow usage further up in the dispatch cycle
Allow configuration of Security salt and cipherSeed from environment variables