Documentation for addind new (site-specific) FHDs

[JannisLi]

At first I had problems adding new FHDs to the multiple spec. scenario
gen_fhd_boots <- generic_fhd_bootstraps[bird_pars$Species]

A documantation might be worsthwile.

Finaly this code worked for me:

crane_fhd_rep<-read.csv(paste0(path,"/crane_fhd_rep"))[,-1] # attation must be made in how to sort the table
crane_fhd_rep <- as.tibble(crane_fhd_rep)
gen_fhd_boots[4]<-list(crane_fhd_rep) # the first 3 row are from the example sample
names(gen_fhd_boots)<-c(names(gen_fhd_boots[1:3]),"Common_Crane")