define openstack-havana repo as bare link

rdo rpm for some reasons comes with puppetlabs and other useless repos
python-lesscpy for rhel is also needed
python-lesscpy install
url has been changed
Merge pull request #126 from MirantisDellCrowbar/sbubnov/feature/rhel-havana/hydrogen/master

https://github.com/crowbar/barclamp-nova_dashboard/pull/126

Merged by devtool for ArkadyKanevsky