Add simple wrapping code for running ansible-playbook
user
```ruby
module Ansible
  class Runner
    def self.run(env_vars, extra_vars, playbook_path)
      run_via_cli(env_vars, extra_vars, playbook_path)
    end

    private

    def self.run_via_cli(env_vars, extra_vars, playbook_path)
      result = %x(#{format_env_vars(env_vars)} #{ansible_command} #{format_extra_vars(extra_vars)} #{playbook_path})
      JSON.parse(result)
    end

    def self.ansible_command
      # TODO add possibility to use custom path, e.g. from virtualenv
      "ansible-playbook"
    end

    def self.format_env_vars(env_vars)
      env_vars.map { |key, value| "#{key}='#{value}'" }.join(" ")
    end

    def self.format_extra_vars(extra_vars)
      "--extra-vars '#{JSON.dump(extra_vars)}'"
    end
  end
end
```
assistant