[fixes #19 & #22] Downgrade bourbon

Downgrade bourbon for compatibility with active-admin/sass 3.0.
using vcr
Remove deprecated and unused test code

There were two depcrecated statements in the Guardfile (:cli and
:version).  I also removed some code that is not used in the
spec_helper.
Fix i18n deprecation warning

This fixes the depcrecation warning by setting the
enforce_available_locales value.  See http://stackoverflow.com/
questions/20361428/rails-i18n-validation-deprecation-warning
Merge pull request #18 from 18F/feature/remove_deprecated_and_unused_test_code

Remove deprecated and unused test code
Merge pull request #19 from 18F/feature/fix_i18n_deprecation_warning

Fix i18n deprecation warning
Merge pull request #11 from adelevie/feature/test_markdownifier

Integrate vcr + test markdownifier
Merge pull request #12 from 18F/feature/fix_scss_cache

[fixes #19 & #22] Downgrade bourbon
Adds db:prepare rake task

Adds a db:prepare rake task to help speed up the dev env setup. This
task will create the database and user based on the information in the
database.yml.