Fix pixel issue with external link icons in footer.

Task-number: QTCREATORBUG-7267

Change-Id: I96e38a03c713fc31ffc9cf975f0d6509bd728993
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>

doc/templates/style/offline.css

@@ -487,6 +487,11 @@ border-top: 1px solid #999;
 padding-top:11px;
 }
 
+.footer a[href*="http://"], a[href*="ftp://"],a[href*="https://"]{
+background-size: 13px 11px;
+padding-left: 16px;
+}
+
 .footerNavi{
 width:auto;
 text-align:right;