Add actions to move and resize windows

[egormanga]

Apparently, this functionality was present in 1.x versions (MOVE_WINDOW & RESIZE_WINDOW), and I don't see any reason why we can't have these features now.

[JoseExposito]

The reason to remove MOVE_WINDOW was because pointer acceleration. The user experience was so bad that I decided to remove it.

About RESIZE_WINDOW, it could be added in the future, nobody complained about it until now, so I guess it is not being missed. I'll leave the issue open, just in case I have time in the future to implement it.