Gets the normalized zone offset ID.
!(p)
The ID is minor variation to the standard ISO-8601 formatted string
for the offset. There are three formats:
!(ul)
!(li){@code Z} - for UTC (ISO-8601)
!(li){@code +hh:mm} or {@code -hh:mm} - if the seconds are zero (ISO-8601)
!(li){@code +hh:mm:ss} or {@code -hh:mm:ss} - if the seconds are non-zero (not ISO-8601)
</ul>
Gets the normalized zone offset ID. !(p) The ID is minor variation to the standard ISO-8601 formatted string for the offset. There are three formats: !(ul) !(li){@code Z} - for UTC (ISO-8601) !(li){@code +hh:mm} or {@code -hh:mm} - if the seconds are zero (ISO-8601) !(li){@code +hh:mm:ss} or {@code -hh:mm:ss} - if the seconds are non-zero (not ISO-8601) </ul>
@return the zone offset ID, not null