(WIP) Update the parameter type annotations for pyqtSignal.__init__

[BryceBeagle]

Resolves #105

The *types annotation is currently broken. Feedback appreciated

test_stubs.py::test_stubs[pyqtsignal.py]
pyqtsignal.py:6: error: Value of type variable "_SignalTypesT" of "pyqtSignal" cannot be "List[Type[str]]"
pyqtsignal.py:8: error: Value of type variable "_SignalTypesT" of "pyqtSignal" cannot be "object"
Found 2 errors in 1 file (checked 1 source file)

Minimal reprduction of issue:
https://mypy-play.net/?mypy=latest&python=3.8&gist=57db3e86d7202dc8ebe4f24965409a3f

Edit: Opened an issue on the mypy issue tracker: python/mypy#9569

[altendky]

Suggested change

	_SignalTypesT = typing.TypeVar("_SignalTypesT", type, typing.List[type])
	_SignalTypesT = typing.TypeVar("_SignalTypesT", typing.Union[type, typing.List[type]])

I can't say I know the reasons for why this works and the separate types don't but... it does. :| Is there something that makes it wrong despite passing?

[altendky]

Err, hold that thought... maybe I didn't test properly here...

[altendky]

Ok, trying again and hoping to be less silly. As is, there is no relationship being created between multiple hints so this can just be an alias instead, I think?

Suggested change

	_SignalTypesT = typing.TypeVar("_SignalTypesT", type, typing.List[type])
	_SignalTypesT = typing.Union[type, typing.List[type]]

(except with a different variable name changed here and at the use sites)

[BryceBeagle]

The issue here is that I need to keep all of the var args of the same type. Using the Union allows for

a = pyqtSignal([int, bool], float)

but this is not allowed by PyQt. You can use only types OR only lists of types

[altendky]

Well, I think my second attempt was less silly... though still not helpful. Humm.