Add airbrake

Airbrake is being used to track our errors through errbit. The
initializer is overridden on deployment.
Fix unprocess[ia]ble typo
Merge pull request #6 from alphagov/airbrake

Add airbrake
Merge pull request #9 from alphagov/fix-unprocessible-typo

Fix unprocess[ia]ble typo
Refactor in memory test persistence

To a more realistic state before switching to postgres
Set up Postgres persistence with sequel gem

Helper scripts for:
* Create database
* Generate migration
* Run migrations

+ @kalleth

Sequel gem
Working Postgres integration with HStore

+ @kalleth
Extract mapper from repository

Mapper is trivial at this point but the presence
of this seam should keep the two concerns separate.
Move load paths and constants to config/env
Move config into YAML files

Load the config by merging together YAML files in the config directory instead
of having a bunch of constants lying around.

Pass the single config hash into the `Application` on initialization.

Also remove all default parameters from `Application` so that it's used in the
same way in test and production.

Conflicts:
	application.rb
	features/support/env.rb
Perform database setup for CI

Provide a separate config used for the app in CI. Alter jenkins script
to run migrations and run rake task to create databases and add
extensions.