Is your feature request related to a problem? Please describe.

I wanted to go ahead and make a PR for adding nil uuid which is a special case. Before doing the work, I just wanted to double check to see if this has been considered before or there are any objections to it.

You can read more about nil uuid https://en.wikipedia.org/wiki/Universally_unique_identifier#Nil_UUID

Describe the solution you'd like

I was thinking about adding nill to the namespace so the user can write the following code:

import { nil } from 'uuid';
console.log(nil()); // => '00000000-0000-0000-0000-000000000000'

I believe that is valid for all versions, so we dont need to implement it under v1, v2, etc.
Let me know your thoughts and I'll get to it.