code: private static List<Map<String, String>> preparePkgs(Map<String, String> pkgs) {
          return pkgs.entrySet().stream()
                  .map(e -> Collections.unmodifiableMap(Stream.of(e)
                          .collect(Collectors.<Map.Entry<String, String>, String, String>
                                  toMap(Map.Entry::getKey, Map.Entry::getValue))))
                  .collect(Collectors.toList());
      }
docs: From a given map (package name -> version), create a list of maps with just one
  element each. This is how Salt requires us to send the 'pkgs' argument when multiple
  packages should be installed or removed.
  
  @param pkgs map with packages (name -> version)
  @return list of maps with one element each