- Removed links to the gov uk stylesheets

- Deleted /stylesheets folder
- Removed sass build from gulpfile
- Changed gov links to usa links
- Changed other govuk styles, like breadcrumbs
- Changed name of uk_components file to us_components
- Fixed a few tests that broke on account of the changes

app/templates/views/organizations/organization/trial-mode-services.html

@@ -14,7 +14,7 @@
   <ul>
   {% for service in current_org.trial_services %}
     <li class="browse-list-item">
-      <a href="{{ url_for('main.service_dashboard', service_id=service.id) }}" class="govuk-link govuk-link--no-visited-state browse-list-link">{{ service['name'] }}</a>
+      <a href="{{ url_for('main.service_dashboard', service_id=service.id) }}" class="usa-link browse-list-link">{{ service['name'] }}</a>
     </li>
   {% endfor %}
   </ul>