[fixed] Hotkeys stop works if we switch between applications

[micheus]

The first time I noticed that I was following a video tutorial and get this problem everytime I switch back to Wings3D.
The mouse actions still works.

I have noticed that using Windows 7 and 10. Not sure if happens with other OS's.

Workaround:
- You have the option to save your project and restart Wings3D, or;
- In order to make Geometry window listen to the keyboard again click on another those small windows (Selection Group, Outiliner, ...) click in some items (sometimes a couple of time) and then hit TAB key until you see the object on Geometry window switch between Flat and Smooth shader mode - that is when the keys get back to be processed by Geometry window. Annoying I know, but it works for now.