Support VCS dependencies

[charliermarsh]

[konstin]

Monotrail implementation: https://github.com/konstin/poc-monotrail/blob/10730ea1a84c58af6b35fb74c89ed0578ab042b6/crates/monotrail/src/install.rs#L380-L411

For monotrail the openssl linked by libgit2 was a huge pain to build and deploy.

If we can, i'd like to use https://docs.rs/gix/latest/gix/, it's native rust, supposed to be faster, has a rustls option and is stable enough that it's used by cargo (e.g. rust-lang/cargo#11448)

[charliermarsh]

Awesome, thank you.