Work out how to set custom lintr parameters in package structure

Currently we have a note flagging that the .lintr file shouldn't exist, we're using this as the config to set custom lintr parameters.


CRAN guidance suggests this kind of file shouldn't be in the root of the package so we'll need to find an alternative way (or bite the bullet and be strict on the 80 character limit for all lines) - https://cran.r-project.org/doc/manuals/R-exts.html#Package-structure-1

Inspect the root .lintr file and read the linked CRAN Package structure guidance first. Determine where custom lintr parameters can live without violating CRAN guidance; done means the package retains its intended lint configuration without the prohibited root file, or adopts the documented 80-character rule.

Written by the indexing model from the issue text.