Convert specs to RSpec 2.14.8 syntax with Transpec

This conversion is done by Transpec 1.7.0 with the following command:
    transpec

* 50 conversions
    from: obj.should
      to: expect(obj).to

* 37 conversions
    from: obj.should_not
      to: expect(obj).not_to

* 16 conversions
    from: == expected
      to: eq(expected)
Cleanup factories definitions

Prepending `generate` with `FactoryGirl` is no longer needed.
Add shoulda-matchers gem for validation specs
Remove calls to `FactoryGirl` in specs
Cleanup uniqueness validation spec
Remove 'private' `hash_flatten` and `hash_fatten` methods

Inline methods into `import_yaml` and `export_yaml` to add a bit of
clarity.
Revamp CopycatTranslation spec

* Reduce duplication in specs that tested importing and exporting
* Use RSpec `expect` syntax
* Don't rely on private I18n API to load translations
First pass through improving RSpec tests

* Focus on readability and clarity with different paragraph blocks for
  setup, test and assertions