kusko_prep: Prepare the Kuskokwim Substock Data for this analysis
In bstaton1/FitSR: Functions to Fit and Summarize SRA Models

Convert the data files from preparing the Kuskokwim River substock data into the format needed by the functions in the FitSR package.

1	kusko_prep(S_dat, H_dat, age_dat, v = NULL, ESSmax = NULL)

`S_dat`	the contents of the data file containing substock spawner abundance
`H_dat`	the contents of the data file containing aggregate harvest
`age_dat`	the contents of the data file containing age composition data
`v`	a vector of relative vulnerabilities to harvest for each substock. Defaults to `NULL`, which results in all substocks being equally vulnerable to harvest
`ESSmax`	a numeric vector of length 1. If you wish to rescale the effective sample size of the age composition data such that the year with the maximum number of fish aged takes on a fixed number, and all other years are scaled proportionately to that number, specify that number here. If left at the default value of `NULL`, then the multinomial effective sample size will be equal to the number of fish successfully aged each year.