Includes tox support for running unit tests.
Small note added to getting-started guide for using
inventory_builder.py

Also adds manual-only unit test.

Also place in global vars and do not repeat the kube_*_config_dir
and kube_namespace vars for better code maintainability and UX.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Currently, the terraform script in contrib
adds etcd role as a child of k8s-cluster in
its generated inventory file.

This is problematic when the etcd role is
deployed on separate nodes from the k8s master
and nodes. In this case, this leads to failures
of the k8s node since the PKI certs required for
that role have not been propogated.

* Add download_localhost for the download_run_once mode, which is
  use the ansible host (a travis node for CI case) to store and
  distribute containers across cluster nodes in inventory.
  Defaults to false.
* Rework download_run_once logic to fix idempotency of uploading
  containers.
* For Travis CI, enable docker images caching and run Travis
  workers with sudo enabled as a dependency
* For Travis CI, deploy with download_localhost and download_run_once
  enabled to shourten dev path drastically.
* Add compression for saved container images. Defaults to 'best'.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Co-authored-by: Aleksandr Didenko <adidenko@mirantis.com>

Squashed commits:
[f9355ea1] Swap order in which we reload docker/socket
[2ca6819c] Reload docker.socket after installing flannel on coreos

Workaround for #569
[9f976e56] Vagrantfile: setup proxy inside virtual machines

In corporate networks, it is good to pre-configure proxy variables.
[9d7142f4] Vagrantfile: use Ubuntu 16.04 LTS

Use recent supported version of Ubuntu for local development setup
with Vagrant.
[50f77cca] Add CI test layouts

* Drop Wily from test matrix
* Replace the Wily cases dropped with extra cases to test separate
  roles deployment

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
[03e162b3] Update OWNERS
[c7b00cae] Use tar+register instead of copy/slurp for distributing tokens and certs

Related bug: https://github.com/ansible/ansible/issues/15405

Uses tar and register because synchronize module cannot sudo on the
remote side correctly and copy is too slow.

This patch dramatically cuts down the number of tasks to process
for cert synchronization.
[2778ac61] Add new var skip_dnsmasq_k8s

If skip_dnsmasq is set, it will still not set up dnsmasq
k8s pod. This enables independent setup of resolvconf section
before kubelet is up.