Use the new vault.centos.org repos. Fix the yum repo configs in the
image if necessary to use these new repos.
Use the standard centos images from the centos registry rather than
custom lsr images from dockerhub.
Add support for centos8. Note that using ansible 2.7 on centos8 requires
setting /usr/bin/python3 to be the ansible python interpreter. Later
versions of ansible have better auto-detection. We can get rid of this
once we drop support for ansible 2.7
Use tox-lsr 1.0.1
Use the new vault.centos.org repos. Fix the yum repo configs in the image if necessary to use these new repos. Use the standard centos images from the centos registry rather than custom lsr images from dockerhub. Add support for centos8. Note that using ansible 2.7 on centos8 requires setting /usr/bin/python3 to be the ansible python interpreter. Later versions of ansible have better auto-detection. We can get rid of this once we drop support for ansible 2.7 Use tox-lsr 1.0.1