Tidy layout of team page

The team page was a bit of a mess:

- invited and active tables didn’t line up
- lots of things were wrapping onto two lines
- the empty fields for when a user didn’t have permissions looked broken

This commit splits each row of the table (not actually a table any more)
onto two lines. First line has the user’s info, second has their
permissions and any associated actions.

app/templates/components/tick-cross.html

@@ -0,0 +1,15 @@
+{% macro tick_cross(yes, label) %}
+  <li>
+    {% if yes %}
+      <span class="tick-cross-tick">
+        <span class="visually-hidden">Can</span>
+        {{ label}}
+      </span>
+    {% else %}
+      <span class="tick-cross-cross">
+        <span class="visually-hidden">Can’t</span>
+        {{ label}}
+      </span>
+    {% endif %}
+  </li>
+{% endmacro %}