Fixing centos6 docker image for pycrytpo too

test/utils/docker/centos6/Dockerfile

@@ -4,6 +4,7 @@ RUN yum -y update; yum clean all;
 RUN yum -y install \
     epel-release \
     file \
+    gcc \
     git \
     make \
     mercurial \
@@ -16,6 +17,7 @@ RUN yum -y install \
 RUN yum -y install \
     PyYAML \
     python-coverage \
+    python-devel \
     python-httplib2 \
     python-jinja2 \
     python-keyczar \
@@ -26,6 +28,7 @@ RUN yum -y install \
     python-setuptools \
     python-virtualenv
 RUN pip install --upgrade jinja2
+RUN rpm -e --nodeps python-crypto; pip install pycrypto
 RUN /bin/sed -i -e 's/^\(Defaults\s*requiretty\)/#--- \1/'  /etc/sudoers
 RUN mkdir /etc/ansible/
 RUN /bin/echo -e '[local]\nlocalhost ansible_connection=local' > /etc/ansible/hosts