Allow changing the title of a window

[JadenV15]

Not sure if this is possible across platforms, but it would be nice to be able to change the title of a pywinctl window obj.

[Kalmat]

Hi! This sounds like a little bit "hacky"... hahahaha!

I am completely sure it is not possible on MacOS. On MS-Windows and Linux I think it is... I will give it a try.

I don't know when I will be able to upload a new version of PyWinCtl module (I have to deeply test everything before, and unluckily I don't have my test environment fully ready). If you need this feature urgently, please let me know.

Nice contribution. Thank you!!!