Pin windows to always be on top

[Jargonius]

Summary of the new feature/enhancement

I think it would be very useful to not have to download a third-party tool to pin windows on top of other windows in windows. An icon or button on the title bar seems like the simplest way to do it. It would be nice if the option to make the window semitransparent was available as well.

[crutkas]

Working on it. #13 is the tracking feature.