Suggest: show the resulting errors in the vignette

[richelbilderbeek]

Dear DAISIEmainland maintainer,

Thanks for DAISIEmainland and having a vignette to demonstrate what it does for a relatively simple parameter set.

Unexpectedly, in the end, when the inference error is calculated (see vignette code below) ...

```{r Calculate error}
errors <- DAISIEmainland::calc_error(
  daisie_data = island,
  ideal_ml = ideal_ml,
  empirical_ml = empirical_ml)
```

... the resulting errors are not displayed on screen, nor interpreted.

I suggest to show the resulting errors and give an intepretation. Sure, maybe the seed needs to be changed to a more interesting-yet-simple scenario :-)

[joshwlambert]

Issue finished, will close when merged to main.