Add form to let users switch basic view on and off

This commit adds radio buttons to the ‘basic view’ page. This will let
users choose whether basic view is on or off for their service.

As before, this page will only be linked to if a service already has
basic view, so this commit does not launch the new feature.

app/templates/views/service-settings/set-basic-view.html

@@ -1,5 +1,5 @@
 {% extends "withnav_template.html" %}
-{% from "components/textbox.html" import textbox %}
+{% from "components/radios.html" import radios %}
 {% from "components/page-footer.html" import page_footer %}
 
 {% block service_page_title %}
@@ -9,7 +9,7 @@
 {% block maincolumn_content %}
 
   <div class="grid-row">
-    <div class="column-five-sixths">
+    <form method="post" class="column-five-sixths">
       <h1 class="heading-large">Basic view</h1>
       <p>
         Basic view lets you restrict a team member to only:
@@ -21,11 +21,13 @@
       <p>
         You’ll get to choose which team members have basic view.
       </p>
+      {{ radios(form.enabled, hide_legend=True) }}
       {{ page_footer(
+        'Save',
         back_link=url_for('.service_settings', service_id=current_service.id),
         back_link_text='Back to settings'
       ) }}
-    </div>
+    </form>
   </div>
 
 {% endblock %}