`FAILED! => {"changed": false, "msg": "AnsibleFilterError: Version comparison: unorderable types: str() < int()"}`

Even though there it kubeadm_token_ttl=0 which means that kubeadm token never expires, it is not present in `kubeadm token list` after cluster is provisioned (at least after it is running for some time) and there is issue regarding this https://github.com/kubernetes/kubeadm/issues/335, so we need to create a new temporary token during the cluster upgrade.

Rename from aggregator-proxy-client to front-proxy-client to match kubeadm design. Added kubeadm support too. Changed to use variables set and not hardcode paths. Still missing cert generation for Vault

1.Disalbe install epel-release rpm on Centos/Redhat
2.Use yum install epel-release

* allow installs to not have hostname overriden with fqdn from inventory
* calico-config no longer requires local as and will default to global
* when cloudprovider is not defined, use the inventory_hostname for cni-calico
* allow reset to not restart network (buggy nodes die with this cmd)
* default kube_override_hostname to inventory_hostname instead of ansible_hostname

Cloud resolvers are mandatory for hosts on GCE and OpenStack
clouds. The 8.8.8.8 alternative resolver was dropped because
there is already a default nameserver. The new var name
reflects the purpose better.

Also restart apiserver when modifying dns settings.

Fix the idx counter to increase too, or you will end up with two same indexes.

If you configure your external loadbalancer to do a simple tcp pass-through to the api servers, and you do not use a DNS FQDN but just the ip, then you need to add the ip adress to the certificates too.

Example config:

```
## External LB example config
apiserver_loadbalancer_domain_name: "10.50.63.10"
loadbalancer_apiserver:
  address: 10.50.63.10
  port: 8383
```

Support ipvs mode for kube-proxy

import_tasks will consume far less memory, so it should be
used whenever it is compatible.

Renamed variable from disable_volume_zone_conflict to volume_cross_zone_attachment and removed cloud provider condition; fix identation

Fix 'no such host' problem reported by commands *kubectl logs* and *kubectl exec*
when cloud_provider is OpenStack

Closes: #2147

kube-proxy is complaining of missing modules at startup. There is a plan
to also support an LVS implementation of kube-proxy in additon to
userspace and iptables

Simplify the number of variables necessary to "just" enable OpenStack
cloud provider. Also add the new options available in K8s 1.9.

Remove blank lines

Update checksum for kubeadm
Use v1.9.0 kubeadm params
Include hash of ca.crt for kubeadm join
Update tag for testing upgrades
Add workaround for testing upgrades
Remove scale CI scenarios because of slow inventory parsing
in ansible 2.4.x.

Change region for tests to us-central1 to
improve ansible performance