Github citations

Use cffr to create repo citations.

Though it needs a package (or at least a DESCRIPTION). If you don’t have that, what we really need is something like this in CITATION.cff

message: 'To cite this repo use:'
type: software
license: MIT
title: 'Repo title'
version: 0.1.0
abstract: What the repo's for
authors:
- family-names: Holt
  given-names: Galen
  email: g.holt@deakin.edu.au
  orcid: https://orcid.org/0000-0002-7455-9275
- family-names: Last
  given-names: First
  email: first.last@email.com
  orcid: https://orcid.org/0000-0002-1234-5678
contact:
- family-names: Holt
  given-names: Galen
  email: g.holt@deakin.edu.au
  orcid: https://orcid.org/0000-0002-7455-9275