Remove the ‘phone’ component

This was used on the old product page to do the graphic of three phones
showing three different messages. We don’t have this any more, so this
‘component’ is unused.

Also removes some unused imports which were a hangover from previous
versions of the product page.

app/templates/components/phone.html

@@ -1,16 +0,0 @@
-{% macro phone(recipient, message) %}
-  <div class="phone">
-    <div class="phone-speaker"></div>
-    <div class="phone-screen">
-      <h2 class="phone-recipient">
-        <span class="visually-hidden">
-          Example text message
-        </span>
-        To: {{recipient}}
-      </h2>
-      <div class="phone-sms">
-        {{ message }}
-      </div>
-    </div>
-  </div>
-{% endmacro %}

app/templates/views/signedout.html

@@ -1,7 +1,3 @@
-{% from 'components/big-number.html' import big_number %}
-{% from "components/banner.html" import banner_wrapper %}
-{% from "components/phone.html" import phone %}
-
 {% extends "fullwidth_template.html" %}
 
 {% block page_title %}