Change donation subtitle

Author: jubalh

pagesource/donate.xml

@@ -1,7 +1,7 @@
     <article id="manual"
              data-sblg-article="1"
              data-sblg-set-title="Profanity, a console based XMPP client - User Guide"
-             data-sblg-set-subtitle="User Guide">
+             data-sblg-set-subtitle="Giving Back">
         <section>
             <h3>Donating</h3>
             <p>Yes, the rumors are true. Developers also have to eat. They also have limited time.</p>