Improve type hints

[Rogdham]

I was not sure what the minimal Python version for type hints is supported, so I tried to be the most compatible. However, I believe it still needs Python 3.5 to be able to import Type from typing.

Things that could be simplified/improved:

• the import of Protocol (Python 3.8)
• using PEP 570 for the arguments to .read and .write (Python 3.8)
• using builtin type instead of Type (Python 3.9)
• importing Callable from collections.abc (Python 3.10)

Things not treated in this PR:

• simplfying bytes | bytearray to bytes (mypy doc): it does not hurt to keep it this way
• proper typing of the **options params: it does not bring a lot to type them properly, and it adds maintainability burden (e.g. you would need to modify the type hints each time you add a new param)