Prepare for social link updates

The full work will be handled in a subsequent patch, but for now
prepare for the update while finalizing the design.

Author: jkatz

templates/base/base.html

@@ -78,16 +78,6 @@
     {%block layoutblock%}{%endblock%}
     <!-- Footer -->
     <footer id="footer">
-      <div class="container">
-        <div class="row">
-          <div class="col-md-12">
-            <ul>
-              <li><a href="https://twitter.com/postgresql"><img src="/media/img/atpostgresql.png" alt="@postgresql"></a></li>
-              <li><a href="https://git.postgresql.org/gitweb/?p=postgresql.git"><img src="/media/img/git.png" alt="Git"></a></li>
-            </ul>
-          </div>
-        </div>
-      </div>
       <!-- Copyright -->
       <div class="container">
         <a href="/about/policies/">Policies</a> |

templates/docs/docspage.html

@@ -169,16 +169,6 @@ <h2>Submit correction</h2>
     </div>
     <!-- Footer -->
     <footer id="footer">
-      <div class="container">
-        <div class="row">
-          <div class="col-md-12">
-            <ul>
-              <li><a href="https://twitter.com/postgresql"><img src="/media/img/atpostgresql.png" alt="@postgresql"></a></li>
-              <li><a href="https://git.postgresql.org/gitweb/?p=postgresql.git"><img src="/media/img/git.png" alt="Git"></a></li>
-            </ul>
-          </div>
-        </div>
-      </div>
       <!-- Copyright -->
       <div class="container">
         <a href="/about/privacypolicy">Privacy Policy</a> |

templates/pages/about/contact.html

@@ -42,9 +42,4 @@ <h2>Press Enquiries</h2>
 <h2>Webmasters</h2>
 
 <p>Contact the PostgreSQL webmasters at <a href="mailto:[email protected]">[email protected]</a>.</p>
-
-<h2>Twitter</h2>
-
-<p>Follow us on <a href="https://twitter.com/postgresql" target="_blank" rel="noopener">Twitter</a>.</p>
-
 {%endblock%}