Text editor sanity

I am not going be subtle about this. *Please* **Convert your tabs to spaces.** **Remove trailing whitespace.**

It is *really* a royal pain in the behind to have to manually fix whitespace differences in GIT and it is making in needlessly annoying for people to contribute.

The code here is quite nice, it is a real pity that these basic standards such as [tabs vs. spaces](https://www.python.org/dev/peps/pep-0008/#tabs-or-spaces) and [trailing newlines](https://stackoverflow.com/questions/1583406/why-does-git-care-about-trailing-whitespace-in-my-files) are not adhered to.

My suggestions:
1. Automatically convert tabs to spaces recursively, e.g. with https://gist.github.com/antivanov/59e00f6129725e9b4404
2. Similarly, remove trailing whitespace https://gist.github.com/dpaluy/3690668 or https://git-scm.com/docs/git-stripspace
3. Add an editorconfig to make sure these standards are automatically adhered to. https://editorconfig.org/
4. Never worry about this again. Ever.

Thanks! :D