Remove 3/4 width column on settings pages

The mesaure on these pages was too short, making them awkward to read.

Also varies the size of text boxes to make them appropriate to the
expected size of content that they will contain.

app/templates/views/service-settings/name.html

@@ -10,26 +10,22 @@
 
   <h1 class="heading-large">Change your service name</h1>
 
-  <div class="grid-row">
-    <div class="column-three-quarters">
 
-      <div class="form-group">
-        <p>Users will see your service name:</p>
-        <ul class="list-bullet">
-          <li>at the start of every text message, eg ‘Vehicle tax: we received your payment, thank you’</li>
-          <li>as your email sender name</li>
-        </ul>
-      </div>
-
-      <form method="post">
-        {{ textbox(form.name) }}
-        {{ page_footer(
-          'Save',
-          back_link=url_for('.service_settings', service_id=current_service.id),
-          back_link_text='Back to settings'
-        ) }}
-      </form>
-    </div>
+  <div class="form-group">
+    <p>Users will see your service name:</p>
+    <ul class="list-bullet">
+      <li>at the start of every text message, eg ‘Vehicle tax: we received your payment, thank you’</li>
+      <li>as your email sender name</li>
+    </ul>
   </div>
 
+  <form method="post">
+    {{ textbox(form.name) }}
+    {{ page_footer(
+      'Save',
+      back_link=url_for('.service_settings', service_id=current_service.id),
+      back_link_text='Back to settings'
+    ) }}
+  </form>
+
 {% endblock %}