Move all major end-user facing parts of the API to zio.http

[jdegoes]

What is not easy to do right now?

The part of the API that a user should invest time in learning is not easy to discover, with some important websocket abstractions being located in the socket package (for example).

Describe the solution you'd like

Relocate all major end-user facing parts of the API to the zio.http package.

Why is it important?

It will improve discoverability of the API, and improve similarity to ZIO, which tries to expose all major parts under import zio._.