Merge branch 'master' into master

.gitignore

.gitlab-ci.yml

.travis.yml.bak

README.md

contrib/terraform/aws/README.md

contrib/terraform/aws/create-infrastructure.tf

contrib/terraform/aws/output.tf

contrib/terraform/aws/templates/inventory.tpl

contrib/terraform/aws/terraform.tfvars.example

contrib/terraform/aws/variables.tf

contrib/terraform/openstack/README.md

docs/ansible.md

docs/coreos.md

docs/getting-started.md

docs/upgrades.md

docs/vars.md

extra_playbooks/inventory

extra_playbooks/roles

extra_playbooks/upgrade-only-k8s.yml

inventory/group_vars/k8s-cluster.yml