Add support for cargo-binstall

[Jackenmen]

cargo binstall provides an easy way to install rust binaries in opposition to building from source as cargo install does. That project along with cargo quickinstall project is aiming to improve the experience that you get with the built-in cargo install that is way slower due to it having to first build the package and all its dependencies.

I've added support for cargo-binstall using these instructions:
https://github.com/ryankurte/cargo-binstall#supporting-binary-installation

You can test that this pkg-url works using this command:

cargo-binstall --pkg-url="{ repo }/releases/download/{ version }/sheldon-{ version }-{ target }.tar.gz" sheldon