py3: add b'' to make a triple quoted string bytes on Python 3
Transformer does not adds b'' in front of triple quoted strings to prevent
converting docs to bytes.
FROM centos:centos6
RUN yum install -y gcc
RUN yum install -y python-devel python-docutils
RUN yum install -y make
RUN yum install -y rpm-build
RUN yum install -y gettext
RUN yum install -y tar
# For creating repo meta data
RUN yum install -y createrepo