Bump Standards-Version to 3.9.3

From: Michael Prokop <mprokop@sipwise.com>

debian/control

@@ -5,7 +5,7 @@ Maintainer: Sipwise Development Team <support@sipwise.com>
 Build-Depends: debhelper (>= 5), iptables-dev (>= 1.4), libglib2.0-dev, libpcre3-dev,
   libxmlrpc-c3-dev (>= 1.16.07) | libxmlrpc-core-c3-dev (>= 1.16.07), libcurl4-openssl-dev | libcurl4-gnutls-dev |
   libcurl3-openssl-dev | libcurl3-gnutls-dev
-Standards-Version: 3.9.2
+Standards-Version: 3.9.3
 Homepage: http://sipwise.com/
 
 Package: ngcp-mediaproxy-ng-daemon