Normalize MIME-types we invented with `/x-ft-` prefix

[Borewit]

MIME media subtypes prefixed with x-ft- are custom-defined by us. They are neither formally registered with IANA nor based on any informal conventions.

These MIME-type mappings changed:

• application/x-lzip ↦ application/lzip (based on https://datatracker.ietf.org/doc/draft-diaz-lzip/)
• application/x.ms.shortcut ↦ application/x-ms-shortcut
• application/x.apple.alias ↦ application/x-ft-apple.alias
• application/x.autodesk.fbx ↦ application/x-ft-fbx
• application/vnd.google.draco ↦ application/x-ft-draco

[sindresorhus]

I don't see any readme update.

[Borewit]

I don't see any readme update.

My push failed, sorry about that.

[sindresorhus]

Looks good now, but this will have to wait until the next major version.