Adding yamllinter to ci steps (#1556)

* Adding yaml linter to ci check

* Minor linting fixes from yamllint

* Changing CI to install python pkgs from requirements.txt

- adding in a secondary requirements.txt for tests
- moving yamllint to tests requirements

roles/vault/tasks/bootstrap/start_vault_temp.yml

@@ -1,5 +1,4 @@
 ---
-
 - name: bootstrap/start_vault_temp | Ensure vault-temp isn't already running
   shell: if docker rm -f {{ vault_temp_container_name }} 2>&1 1>/dev/null;then echo true;else echo false;fi
   register: vault_temp_stop_check
@@ -13,7 +12,7 @@
            -v /etc/vault:/etc/vault
            {{ vault_image_repo }}:{{ vault_version }} server
 
-#FIXME(mattymo): Crashes on first start with aufs docker storage. See hashicorp/docker-vault#19
+# FIXME(mattymo): Crashes on first start with aufs docker storage. See hashicorp/docker-vault#19
 - name: bootstrap/start_vault_temp | Start again single node Vault with file backend
   command: docker start {{ vault_temp_container_name }}