Upgraded PowerDNS to 3.4.7 using Jessie Backports

pdns/Dockerfile

@@ -1,11 +1,11 @@
-FROM debian:jessie
+FROM debian:jessie-backports
 MAINTAINER Fabio Rauber <fabiorauber@gmail.com>
 
 ENV DNSSEC="yes" \
     APIKEY="" 
 
 RUN apt-get update && \
-    DEBIAN_FRONTEND=noninteractive apt-get install -q -y pdns-server pdns-backend-mysql mysql-client && \
+    DEBIAN_FRONTEND=noninteractive apt-get install -q -y -t jessie-backports pdns-server pdns-backend-mysql mysql-client && \
     rm /etc/powerdns/pdns.d/*.conf && rm /etc/powerdns/*.conf && \
     apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*