Improves EPEL and RDO repo setup

This patch improves repo setup. In case of EPEL it also enables/disables
EPEL repo according to configuration. In case of RDO it's installed on
each host if the repo is installed locally.

Fixes: rhbz#974971, rhbz#990642

Change-Id: I3a1f77061439f1072a0932918384b939babcd3e0
Merge "Improves EPEL and RDO repo setup"