Add initial support for cargo

[ssbarnea]

• check for Cargo.toml
• cargo --list --color=never does show installed commands but they might be too many as they include aliases. No documented way to expose them in a machine friendly format.

References

• https://doc.rust-lang.org/cargo/commands/cargo-build.html
• https://github.com/sharkdp/bat as sample project using cargo