Commit the Cargo.lock file

[carschandler]

Was trying to package leetup using nix, and it requires the Cargo.lock file to be in the source repository:

From the nixpkgs manual:

Per the instructions in the Cargo Book best practices guide, Rust applications should always commit the Cargo.lock file in git to ensure a reproducible build. However, a few packages do not, and Nix depends on this file, so if it is missing you can use cargoPatches to apply it in the patchPhase. Consider sending a PR upstream with a note to the maintainer describing why it’s important to include in the application.
The fetcher will verify that the Cargo.lock file is in sync with the src attribute, and fail the build if not. It will also will compress the vendor directory into a tar.gz archive.