Lorenzen M not incrementing by season

[Rick-Methot-NOAA]

A test of Lorenzen M with seasons showed that it was using the same length-at-age for each season, so produced the same M for each season. This needs attention. Should create a new M option that is Lorenzen M with seasons to maintain backward compatibility.

[Rick-Methot-NOAA]

code was referring to just first season length-at-age, and it had an incorrect reference to Bseas(g).
Both are fixed.
Note that existing models that uses Lorenzen M and seasons will now see a different result because of the, now corrected, seasonality in M.