Update docs

[bmwant]

Changes

• Add curl usage examples with http2
• Add openssl certificate generation command
• Fix readlines methods
• Fix async/await syntax
• Minor typos

[Kriechi]

Suggested change

	To use it with our server though, you will need to invoke it with a different
	To use it with a ``python-hyper/h2``-based server, you can invoke it with a different

[bmwant]

In this context I meant to use it with the server from this example, not any arbitrary hyper/h2-based server (as generally you will serve it with TLS), so you should or you have to is probably better.

[bmwant]

@Kriechi addressed your concerns, still have one open regarding phrasing, but otherwise should be ready for another check

[Kriechi]

Thanks for making the changes! Looks good to me overall.

Seems the docs building with sphinx broke - likely unrelated to this PR though... I'll look into it in the next days, unless you beat me too it 😄

[bmwant]

@Kriechi fixed tox -e docs by bumping Sphinx version used

[Kriechi]

Thanks! 🎉