Automate a bit more releasing a version of this crate

[tomaka]

Releasing a new version of libp2p is very painful. One has to bump the version of every crate in all the Cargo.tomls, then publish packages one by one in the correct order (as they depend on each other).

Additionally, since there are cyclic dependencies within dev-dependencies, one has to actually tweak the Cargo.tomls right before publishing to remove dev-dependencies, and use cargo publish --allow-dirty.

The fact that this is so painful makes it really annoying to release hotfixes for example.

[LegNeato]

We have similar constraints to the first requirement in https://github.com/graphql-rust/juniper if you want to see how we solved it.

[thomaseizinger]

Closing in favor of #2902.