* Upgrade Tonic to Tokio 1.0
Work in progress for updating Tonic to Tokio 1.0. Since tower has not
been released to crates.io, a git dependency is taken instead.
* Upgrade Tonic to Tokio 1.0 phase 2
* tonic: remove tower-* deps
* Apply suggestions from code review
Co-authored-by: Ed Marshall <[email protected]>
Co-authored-by: Lucio Franco <[email protected]>
