Add ability to delete docs

[randombenj]

Implement something like DELETE /api/PROJECT/VERSION

[bryantfhayes]

I would definitely use this!

[randombenj]

Before we merge this we need to implement some kind of token.
As discussed with @fliiiix the simplest aproach would be to generate a uuid
when a project is created, which is then returned after creation.
When one wants to delete a version he has to pass this token.