Code overwrites OM@cpars$AddIerr

[quang-huynh]

There appears to be pathological behavior where I specify OM@cpars$AddIerr yet it is overridden when AC is NA (index occurs every other time step)

I believe the issue occurs here: https://github.com/Blue-Matter/MSEtool/blob/master/R/Data_make_update.R#L1668

I can specify OM@cpars$Ierr_y but it seems like a highly inelegant solution and does not work when n.ind > 1 (all indices will have same error structure)

An alternate solution is to sample with AC = 0 when all(is.na(AC)) is TRUE and with SD = OM@Iobs when all(is.na(SD)) is TRUE