README no longer builds

[mhpob]

Error:

Quitting from lines 63-68 [ex1 run simulation2] (README.Rmd)
                                                                                                                               
Error in `if (mpar$model == "bcrw.coa" & length(mpar$bl) > 1) ...`:
! the condition has length > 1

Seems to be an issue with sim_fish as my.par$model is c("bcrw.coa","bcrw")
https://github.com/ianjonsen/simfish/blob/main/R/sim_fish.R#L90-L93

[mhpob]

Looking deeper, the issue is in sim_par and was introduced in d00f930#diff-e3c066cb79ef17a4b7c8875e6ebb8f06a852d9358057b7513f1fd6d80ceff617R73