define openstack-havana repo as bare link

rdo rpm for some reasons comes with puppetlabs and other useless repos
fix executing keystone-manage
keystone conf dir comes with root permissions from rdo repo
temporary disable ec2 registration under centos

we cannot create ec2 credentials with service token. this is temporary workaround.
Merge pull request #151 from MirantisDellCrowbar/sbubnov/bug/rhel-havana/hydrogen/master

https://github.com/crowbar/barclamp-keystone/pull/151

Merged by devtool for ArkadyKanevsky