We currently have spread out package/host management to multiple
roles, sometimes repeating ourselves in the process (see
pip_install and openstack_hosts overlap)
That is against Ansible principles, and we should have one role
that configures the minimum (to run openstack), applying it to
all the nodes, maybe behaving slightly differently depending on
some parameters. Here that parameter is if the host is a container
or not. If the host is a container, all the physical host
configuration (kernel and sysctl) is be skipped, the
rest of the configuration (packages/repos) still applies.
This needed a refactor to split the tasks into those two group
while remaining efficient and avoid multiple back and forth
of package installs/removal. For that last point, new defaults
variables were introduced, allowing overrides per host/group.
A node now member of a group x can now directly use this role
to setup all its necessary repos and keys.
Last, but not least, this override mechanism can now easily
trigger pip_install role, which can from now on, be removed
from every role. On top of that pip_install role can now
remove its repo management, and focus on installing pip on
hosts that don't have a proper version of pip installed.
Change-Id: Ibf145e561c80a12055bd4d5dca3914c4d495a748
f8a150cc76