Ability to reference/download the latest package contents

[vshymanskyy]

Currently it's possible to download a wasm file from wapm io, i.e following a link:
https://registry-cdn.wapm.io/contents/vshymanskyy/wasm3/0.4.6/build/wasm3.wasm

It would be nice if we could download the latest version without specifying the exact version, like
https://registry-cdn.wapm.io/contents/vshymanskyy/wasm3/latest/build/wasm3.wasm

Also, in this case it would be beneficial to access the wapm.toml file, i.e:
https://registry-cdn.wapm.io/contents/vshymanskyy/wasm3/latest/wapm.toml

I'd like to use WAPM registry directly in some of my CI scripts.