* 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
Based on #718 introduced by rsmitty.
Includes all roles and all options to support deployment of
new hosts in case they were added to inventory.
Main difference here is that master role is evaluated first
so that master components get upgraded first.
Fixes#694
