Add some filtering to 55-cache-devsatck-repos to handle centos7, which
actually gets setup with a DISTRO_NAME of rhel7 in devstack
Update the readme file to highlight the options for building other
images.
"DISTRO=centos7 ./tools/build-image.sh" creates a workable centos7
qcow image with this change and a d-i-b that includes
Ie24033468b78587ea87188ee1b843b26895798ff
Change-Id: Ida38cba0a303ab77432d5d354f1952e00ebfa00e
This repo was created from filter branching the openstack-infra/
config repo. This process brought a lot of cruft with it in the
form of directories that we no longer need. This patch removes
that cruft so we begin with a tidier repo.
Change-Id: Ibffad1b11c0c5f84eedfb0365369f60c4961a0f3