bind: specify bind version in apt install command

Dockerfile

@@ -1,15 +1,16 @@
 FROM sameersbn/ubuntu:14.04.20161014
 MAINTAINER [email protected]
 
-ENV DATA_DIR=/data \
- BIND_USER=bind \
- WEBMIN_VERSION=1.820
+ENV BIND_USER=bind \
+ BIND_VERSION=1:9.9.5 \
+ WEBMIN_VERSION=1.820 \
+ DATA_DIR=/data
 
 RUN rm -rf /etc/apt/apt.conf.d/docker-gzip-indexes \
  && wget http:https://www.webmin.com/jcameron-key.asc -qO - | apt-key add - \
  && echo "deb http:https://download.webmin.com/download/repository sarge contrib" >> /etc/apt/sources.list \
  && apt-get update \
- && DEBIAN_FRONTEND=noninteractive apt-get install -y bind9 webmin=${WEBMIN_VERSION}* \
+ && DEBIAN_FRONTEND=noninteractive apt-get install -y bind9=${BIND_VERSION}* webmin=${WEBMIN_VERSION}* \
  && rm -rf /var/lib/apt/lists/*
 
 COPY entrypoint.sh /sbin/entrypoint.sh