[feature request] Add a way to copy Cargo.toml snippet to the clipboard

I love searching crates on lib.rs. When it I found what I wanted, I need to add the library to my Cargo.toml. However, I think that this last step could be improved.

Currently, I open the dropdown menu at the top, then click on crates.io, wait for the page to load, and finally click on the "Copy Cargo.toml snippet to the clipboard".

It would be a nice addition if this button was directly accessible from lib.rs.

I think such button could be added either in the dropdown menu (which is accessible from any page, but already quite full), or at the maybe at the top of the index page of the crate.