Adds window size and position assertions for MacOS

[mnmaita]

This PR tries to address Issue #700 .

Remarks:

• I'd like to get rid of the magic numbers here and create constants for these boundaries, what would be the best way to do this?

• I've added custom messages to the assertions, I don't know if this is desirable or not.

• Big plus, a MacOS system user that's able to test this would be awesome 😄.

[Cobrand]

For the first one, you can have a const i32 variable inside the function WINDOW_POS_LIMIT and WINDOW_WIDTH_LIMIT or something, and then use them instead of your magic numbers.

const do not take any place in memory or in the stack, they'll be replaced as is, much like defines in C.

Otherwise it looks good to me. The alternative would be to output a Result<(), SomeKindOfError>, so that the library user can see what could go wrong at compile without his program crashing in his face.

[mnmaita]

@Cobrand Thank you for your guidelines. I want to output a Result<(), WindowSetError> (I'll need to create an enum to achieve this), but wouldn't this break the API? Right now, some of these functions already return an IntegerOrSdlError.

[Cobrand]

@mnmaita Sorry for the late response. Breaking API changes make sense if there is a valid reason behind it, and this is a perfectly valid reason.

[mnmaita]

No problem @Cobrand, I'm very busy lately but I'll get to this soon.