Emulation window position

[mark_k]

WinUAE seems to save the last-used position of the top-left of the emulation window to the registry. When running WinUAE next time, the emulation window opens with its top-left corner in that position.

That can be slightly annoying in cases like this:
- Use a config with large window all on-screen, e.g. accelerated/JIT/Workbench
- Load an A500-like config with much smaller window to run a demo etc. Position the emulation window near the bottom right of the desktop.
- Load the large-window config again. When the emulation window opens its top-left corner is in the same position as the smaller window from the previously-used config. So it's partly off-screen.

Not sure what the best or simplest way to handle that is. Maybe save the last-used window size too, and if there's a big difference ignore the saved top-left position? Or move the top-left so the window would be fully on-screen, if the last-used size/position was all on-screen?