[CentOS] Ansible repository shenanigans in EL7

For those not aware ansible has been deprecated in RHEL7 from the extras
repository.

In the RHEL specific world it's now in an optional "product" (basically an
optional subscription) that is part of any RHEL subscription, but it's opt
in.

As a result ansible is back in the EPEL7 repository for 2.5.0+ , having
been removed for  ansible 2.4.2 when it got introduced to the  RHEL extras
repo.

I have no idea what, if anything, the CentOS team will do with the ansible
in the CentOS7 extras repository.