docs: public static Config parse(Properties properties) {
          ConfigBuilder config = new SimpleConfig();
          for (Object o : new TreeSet<>(properties.keySet())) {
              String key = o.toString();
              if (isPositional(key)) {
                  String entryKey = entryKey(key);
                  if (config.containsKey(entryKey)) {
                      config.getCollection(entryKey).add(properties.getProperty(key));
                  } else {
                      ArrayList<Object> sequence = new ArrayList<>();
                      sequence.add(properties.getProperty(key));
                      config.putCollection(entryKey, sequence);
                  }
              } else {
                  config.put(key, properties.getProperty(key));
              }
          }
          return ImmutableConfig.copyOf(config);
      }