Added Brakeman security scanner.
Added RSpec testing framework.
Added FactoryGirl to replace database fixtures in tests.
Removed "test" directory. Created "spec" subdirectories.

We are using Rspec instead of Test::Unit, we don't need the "test" directory created by Rails.
Specify Ruby version in gemfile.
Minor change in the Gemfile.
Added staging environment.
Use Sqlite database for testing/development, and Postgresql for staging/production.
Added Simplecov gem to get code coverage.
Generated the database schema for the first time.
Added Capybara-webkit for acceptance testing.
Use database_cleaner to clean database between tests.

This is necessary to test features involving javascript with capybara-webkit.