This commit is here just to shore everything up before embarking on yet
another full refresh of the config.
This is likely going to be the last commit and it is very important if
you are using this repo to check for a hopefully newly created "NIVM"
repo.
(Note: this may take time, I will archive this repo when I have a
working NIVM)
Add support for checking if `theme.sh` is installed and if so attempt to
choose a matching theme colour.
Marked as breaking as this is untested outside of my environment
