Easy way to generate "other" section for references

[mikeroswell]

Trying to set up the references section, and unsure what to add in the _pkgdown.yml file so the references section is comprehensive without explicitly listing all the functions that aren't categorized elshewhere (see e.g. https://stackoverflow.com/q/45886789/8400969. Would be great to have a user-friendly way to have a catchall for exported functions not listed elsewhere in the reference!