Crates.io release workflow

When releasing to crates.io:

• Remove path dependencies
• (Possible) Updates:
  • html_root_url in core/lib.rs
  • Check Cargo.toml versions and documentation urls.
  • README.md (including version information)
  • Check lib.rs/ffi crate info for DPDK versions, as well as versions ok'ed for Rust, rr.
  • Update CHANGELOG.md when necessary
  • Create/upload git tag for reach release
  • Check release against sandbox-container Rust/DPDK/rr versions
  • Update examples and bench Cargos w/ core versions
• Docs
  • run docs for core (and ffi) via:

    cargo +nightly doc --lib --no-deps --features capsule-ffi/rustdoc,full