Contributing page should recommend using index.d.ts ?

[AJamesPhillips]

The contributing page states

Naming the file
Try to use a simple lowercase identifier as name of the definition file, like library.d.ts or node-hoge.d.ts

Should that read "use index.d.ts for all libraries"? If so then I'm happy to prepare a pr, just let me know.

[AJamesPhillips]

Looks like this is duplicated on: https://github.com/DefinitelyTyped/DefinitelyTyped Perhaps we can just redirect to the README instead?