(suggestion) Remove sub directories

[MortezaHeydari97]

Hi,
Sometimes we need the pure domain only.
So I've a new suggestion to implement a new option to remove sub directories of the URL.

[sindresorhus]

Yeah, there could be a removePath option that defaults to false.

[millette]

Related to #190 but I only wanted to remove certain sub directories.

[sindresorhus]

I think we could let it also accept a function that is provided the path components and is expected to return the new path components.