Suggestions for the Javadoc of methods having a CodeList<?> return type
(replace "NewCodeList" and "3.1" by appropriate values):

     *
     * <div class="warning"><b>Upcoming API change — specialization</b><br>
     * The argument type will be changed to the {@code NewCodeList} code list when GeoAPI will provide it
     * (tentatively in GeoAPI 3.1). In the meantime, users can define their own code list class as below:
     *
     * {@snippet lang="java" :
     *   final class UnsupportedCodeList extends CodeList<UnsupportedCodeList> {
     *       private static final List<UnsupportedCodeList> VALUES = new ArrayList<UnsupportedCodeList>();
     *
     *       // Need to declare at least one code list element.
     *       public static final UnsupportedCodeList MY_CODE_LIST = new UnsupportedCodeList("MY_CODE_LIST");
     *
     *       private UnsupportedCodeList(String name) {
     *           super(name, VALUES);
     *       }
     *
     *       public static UnsupportedCodeList valueOf(String code) {
     *           return valueOf(UnsupportedCodeList.class, code);
     *       }
     *
     *       &#64;Override
     *       public UnsupportedCodeList[] family() {
     *           synchronized (VALUES) {
     *               return VALUES.toArray(new UnsupportedCodeList[VALUES.size()]);
     *           }
     *       }
     *   }
     *   }
     * </div>
     *
