Updated Postgres URL in CentOS 6 Dockerfile.
The link was pointing to an rpm package that has since been
replaced on the upstream server.
diff --git a/support/packaging/centos/centos6.dockerfile b/support/packaging/centos/centos6.dockerfile
index 73c9637..c8471df 100644
--- a/support/packaging/centos/centos6.dockerfile
+++ b/support/packaging/centos/centos6.dockerfile
@@ -27,7 +27,7 @@
# PostgreSQL repo for libevent2.
RUN rpm -Uvh --replacepkgs \
- http://yum.postgresql.org/9.5/redhat/rhel-6-x86_64/pgdg-centos95-9.5-3.noarch.rpm
+ http://yum.postgresql.org/9.5/redhat/rhel-6-x86_64/pgdg-redhat-repo-latest.noarch.rpm
# Setup JDK
RUN echo -e 'export JAVA_HOME=/usr/lib/jvm/java-openjdk' >> /etc/profile.d/java-home.sh