Fix wrong field sizes in PGN 60928 ISO Address Claim.

Some field sizes as well as names does not match the information publicly available at http://www.nmea.org/Assets/20140710%20nmea-2000-060928%20iso%20address%20claim%20pgn%20corrigendum.pdf

Most differences have been fixed for the PGN 60928, resulting in a correct total length of eight bytes.

The same fields are found in PGN 65240 *ISO Commanded Address* and as far as I understand, the ```NAME``` information consisting of all fields in the *ISO Address Claim* must match exactly, so the field format should also be the same. However, I have not modified this part yet, since I do not have a definite source. Especially the total message length for PGN 65240 cannot be correct counting in the additional *New Source Address* field.

I would be happy to adjust this if anyone could provide a real sample of an *ISO Commanded Address* PGN, which I have never seen so far.