code: public Map<String, String> getMapAttribute(String name, String defaultValue) {
          return mapSplit(getAttribute(name), defaultValue);
      }
docs: Returns an attribute's map value from this JAR's manifest's main section.
  The attributes string value will be split on whitespace into map entries, and each entry will be split on '=' to get the key-value pair.
  The returned map may be safely modified.
  
  @param name the attribute's name