Add intro text

source/sponsors.html.twig

@@ -2,6 +2,11 @@
 layout: page
 title: Sponsors
 ---
+<div>
+  <p>DrupalCamp Bristol would like to say a massive <strong>THANK YOU!</strong> to all of our incredible sponsors. Without your support, this event would never have been possible.</p>
+  <p>If you'd like to get involved with sponsorship, head over to our <a href="/sponsorship">Sponsorship</a> page. We'll be on the lookout for new sponsors up until the day of the event.</p>
+</div>
+
 {% for level in site.sponsorship_levels %}
   {% set sponsors = site.sponsors[level] %}
   {% if sponsors %}