Allow setting of caseworking on a user

This commit changes the form that the user sees when inviting or editing
another user, if the service has the ‘caseworking’ permission set.

This will allow creating a new type of user, one who only has the
`send_messages` permission, without the `view_activity` permission.

We are doing this because we think there are a number of services with a
lot of users who don’t need to see the dashboard, or the other team
members, and that we can make a simpler interface for these users.

app/templates/components/radios.html

@@ -135,3 +135,9 @@
     </fieldset>
   </div>
 {% endmacro %}
+
+{% macro conditional_radio_panel(id) %}
+  <div class="js-hidden panel panel-border-wide conditional-radios-panel" id="panel-{{ id }}">
+    {{ caller() }}
+  </div>
+{% endmacro %}