Added ability to get screen resolution/size

[olumidesan]

Hi.

Was looking to add the ability to get the screen size of the current system, as I always have to use another library (pyautogui) to do that. Would be nice if pynput could have a small utility function that does that.

Not sure if the PR follows your folder structure, but I really just wanted to show the basic functionality itself, leaving folder logistics for later. So, I added a screen module and a get_screen_size() function that, essentially, loops through the borders of the screen to get the screen size.

Let me know what you think.

A simple test:

>>> from pynput.screen.utils import get_screen_size
>>> get_screen_size()
(1920, 1080)

[moses-palmer]

Thank you for your contribution.

You may want to have a look at #74 which adds this functionally by querying the operating system. Please note that it has not been merged, since I felt the API to be a bit limiting. Given that you have also required this functionality, perhaps it is time to put in the effort to merge it.

Since this PR adds the same capability to the library as another one, I will close this.

[olumidesan]

Alright, thanks.