code: public static Map dotDissoc(final Map map, final String pathString) {
          if (pathString == null || pathString.isEmpty()) {
              throw new IllegalArgumentException(PATH_MUST_BE_SPECIFIED);
          }
          if (!pathString.contains(SEPARATOR)) {
              map.remove(pathString);
              return map;
          }
          final Object[] path = pathString.split(SEPARATOR_REGEX);
          return MapApi.dissoc(map, path);
      }
docs: Dissociates value by specified path.
  @param map subject original map
  @param pathString nodes to walk in map path of value
  @return original map