Alright, I got tired of confusing myself with the same-named
outer and inner package.
Keep in mind that every frontend implementation is supposed to be
its own independent project where etiquette is nothing but a
dependency. So the name backend is not ambiguous with the etiquette
backend.
Added a styleguide.md file to refer back to.
Since voussoirkit is a library it feels better to have it below
the rest of the library and above the local project imports.
