- 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/components/previous-next-navigation.html

@@ -4,7 +4,7 @@
       <ul class="group">
         {% if previous_page %}
           <li class="previous-page">
-            <a class="govuk-link govuk-link--no-visited-state" href="{{previous_page['url']}}" rel="previous" >
+            <a class="usa-link" href="{{previous_page['url']}}" rel="previous" >
               <span class="pagination-part-title">
                 <svg class="pagination-icon" xmlns="http://www.w3.org/2000/svg" height="13" width="17" viewBox="0 0 17 13">
                   <path fill="currentColor" d="m6.5938-0.0078125-6.7266 6.7266 6.7441 6.4062 1.377-1.449-4.1856-3.9768h12.896v-2h-12.984l4.2931-4.293-1.414-1.414z"/>
@@ -17,7 +17,7 @@
         {% endif %}
         {% if next_page %}
           <li class="next-page">
-            <a class="govuk-link govuk-link--no-visited-state" href="{{next_page['url']}}" rel="next">
+            <a class="usa-link" href="{{next_page['url']}}" rel="next">
               <span class="pagination-part-title">
                 {{next_page['title']}}
                 <svg class="pagination-icon" xmlns="http://www.w3.org/2000/svg" height="13" width="17" viewBox="0 0 17 13">