DECODR Line.Sta Calculator Negative Longitude Fix

The line.sta calculator uses station position GPS latitude & longitude to calculate the actual CalCOFI station Line.Sta. There was a problem when a negative (W) longitude was used from the YYMMcasts.csv, saved by CESL. A negative longitude causes the decimal longitude parsing back to degrees to be negative, so the longitude minutes were miscalculated. This resulted in an incorrect 'actual line' (Ac_Line) & 'actual sta' Ac_Sta calculations during the csv>database conversion. 

DECODR1410 now checks for a longitude < 0 and multiplies it by -1 to insure a positive longitude is parsed. The decimal longitude (Lon_Dec) and longitude degrees are still reported as a negative. So this change does not affect the outputted data signs, only the internal calculations.