Rename footer.html to footer.php

The new website design has variable data in the footer based
on its distributed hpr instance.

hub/request.php

@@ -64,7 +64,7 @@ if( !isset($row_dupe) or $num_from_this_ip != 0 ) {
   echo "</pre>\n";
   echo "<hr />\n";
   file_put_contents($naughtyfile, date('Y-m-d\TH:i:s\Z') . "\t" . getUserIPAdress() . "\tExisting Request\t" . $_SERVER['REQUEST_URI'] . "\t" . $_SERVER["HTTP_USER_AGENT"] . "\n" , FILE_APPEND | LOCK_EX );
-  include("footer.html");
+  include("footer.php");
   exit;
 }
 
@@ -207,5 +207,5 @@ include 'header.php';
 </main>
 
 <?php
-include 'footer.html'; 
+include 'footer.php'; 
 ?>