- 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/inbound-sms-admin.html

@@ -52,7 +52,7 @@ Inbound SMS
               {% endif %}
               </td>
               <td>
-                  <a href="{{ url_for('main.service_dashboard', service_id=value.service.id) }}" class="govuk-link govuk-link--no-visited-state govuk-!-font-size-24 govuk-!-font-weight-bold">{{ value.service.name }}</a>
+                  <a href="{{ url_for('main.service_dashboard', service_id=value.service.id) }}" class="usa-link govuk-!-font-size-24 govuk-!-font-weight-bold">{{ value.service.name }}</a>
               </td>
           </tr>
           {% endfor %}