renamed internal popup managment to make it clear that popups are closed and not removed when being closed
renamed internal popup managment to make it clear that popups are closed and not removed when being closed

xranby/nifty-gui,Ryszard-Trojnacki/nifty-gui,atomixnmc/nifty-gui,relu91/nifty-gui,mkaring/nifty-gui,void256/nifty-gui,Ryszard-Trojnacki/nifty-gui,atomixnmc/nifty-gui,bgroenks96/nifty-gui,gouessej/nifty-gui,Teencrusher/nifty-gui,Teencrusher/nifty-gui,void256/nifty-gui,bgroenks96/nifty-gui