Pulling upstream into master
> Note the `git fetch upstream` isn't needed when the `-f` option is used when adding the remote:
>
> > With -f option, git fetch is run immediately after the remote information is set up.
>
> https://git-scm.com/docs/git-remote#_commands
So remove that. This PR is good for merge now so merging.
* add luacheck workflow and config
* replace 'digiline' with 'digilines'
* fix whitespace
* fix most variable warnings
* piston.lua and movestone.lua have inline ignores for some hard to fix code
* increase line length for now
