def machine_names_and_options
      {}.tap do |r|
        @config.vm.defined_vms.each do |name, subvm|
          r[name] = subvm.options || {}
        end
      end
    end
def machine_names_and_options
      {}.tap do |r|
        @config.vm.defined_vms.each do |name, subvm|
          r[name] = subvm.options || {}
        end
      end
    end
Returns a list of the machine names as well as the options that
 were specified for that machine.

 @return [Hash<Symbol, Hash>]