Remove ?> marker from config-dist.php, which will prevent people breaking...

Remove ?> marker from config-dist.php, which will prevent people breaking their site with whitespace issues.

Only changing this file because it's the one people touch the most.
(cherry picked from commit 0defc9c3)

htdocs/config-dist.php

@@ -73,4 +73,4 @@ $cfg->dbprefix = '';
 // this is a big security hole.
 $cfg->dataroot = '/path/to/uploaddir';
 
-?>
+// closing php tag intentionally omitted to prevent whitespace issues