Redo reference docs.

[aaugustin]

Remove sphinx-autodoc-typehints and use native autodoc features
instead, mainly because I can't find a workaround for:
https://github.com/agronholm/sphinx-autodoc-typehints/issues/132

Re-introduce the "common" docs, else linking to send() and recv()
is a mess.

[aaugustin]

• src/websockets/__init__.py
• src/websockets/__main__.py
• src/websockets/auth.py
• src/websockets/client.py
• src/websockets/connection.py
• src/websockets/datastructures.py
• src/websockets/exceptions.py
• src/websockets/extensions/__init__.py
• src/websockets/extensions/base.py
• src/websockets/extensions/permessage_deflate.py
• src/websockets/frames.py
• src/websockets/headers.py
• src/websockets/http.py
• src/websockets/http11.py
• src/websockets/imports.py
• src/websockets/legacy/__init__.py
• src/websockets/legacy/auth.py
• src/websockets/legacy/client.py
• src/websockets/legacy/compatibility.py
• src/websockets/legacy/framing.py
• src/websockets/legacy/handshake.py
• src/websockets/legacy/http.py
• src/websockets/legacy/protocol.py
• src/websockets/legacy/server.py
• src/websockets/server.py
• src/websockets/streams.py
• src/websockets/typing.py
• src/websockets/uri.py
• src/websockets/utils.py
• src/websockets/version.py

---

• docs/reference/client.rst
• docs/reference/common.rst
• docs/reference/exceptions.rst
• docs/reference/extensions.rst
• docs/reference/index.rst
• docs/reference/limitations.rst
• docs/reference/server.rst
• docs/reference/types.rst
• docs/reference/utilities.rst