Updating site to use USWDS styles (#509)

* Updated header and footer
* Updated fonts
* Moved files around and updated gulpfile to correct the build process when it goes to production
* Adjusted grid templating
* Added images to assets
* Update app/templates/components/uk_components/footer/template.njk

Co-authored-by: Steven Reilly <stvnrlly@users.noreply.github.com>

app/templates/views/support/bat-phone.html

@@ -16,25 +16,25 @@
     {{ page_header('Out of hours emergencies')}}
     <div class="govuk-grid-row">
       <div class="govuk-grid-column-two-thirds">
-        <p class="govuk-body">
+        <p>
           First, check the
           <a class="govuk-link govuk-link--no-visited-state" href="https://status.notifications.service.gov.uk">system status page</a>.
           You do not need to contact us if
           the problem you’re having is listed on that page.
         </p>
-        <p class="govuk-body">
+        <p>
           Otherwise, contact us using the emergency email address we
           gave you or your service manager when we made your service live.
         </p>
-        <p class="govuk-body">
+        <p>
           We’ll reply within 30 minutes and give you hourly updates
           until the problem’s fixed.
         </p>
-        <p class="govuk-body">
+        <p>
           We do not offer out of hours support if your service is in
           trial mode.
         </p>
-        <h2 class="heading-medium">Any other problems</h2>
+        <h2 class="font-body-lg">Any other problems</h2>
         <p class="bottom-gutter-2">
           <a class="govuk-link govuk-link--no-visited-state" href="{{ url_for('main.feedback', ticket_type='report-problem', severe='no') }}">Fill in this form</a>
           and we’ll get back to you by the next working day.