docs: update docstrings with deprecated directive

[IronCore864]

Update docstrings to use sphinx deprecated directive.

[tonyandrewmeyer]

Nice, thanks!

What do you & @benhoyt think about putting a deprecation notice on OpenedPort here as well? With a message to use Port instead, and the version either 2.13 as an official deprecation or 2.7 which is when it essentially was?

[benhoyt]

A deprecation notice on OpenedPort sounds good to me!

[IronCore864]

It seems if I add a docstring on a global variable:

OpenedPort = Port
"""Alias for backwards compatibility.

.. deprecated:: 2.7.0
    Use :class:`Port` instead.
"""

it does not show up in sphinx autodoc.
Shall I make it a new class so that I can add a docstrig to it?

class OpenedPort(Port):
    """Alias for backwards compatibility.

    .. deprecated:: 2.7.0
        Use :class:`Port` instead.
    """

[benhoyt]

Thanks for the updates!