Call EventHandler::pump() first in game loop

According to the SDL documentation:
https://wiki.libsdl.org/SDL2/SDL_PollEvent
> The common practice is to fully process the event queue once every frame, usually as a first step before updating the game's state

In particular, we probably don't want to put event polling between drawing and swapping of the back buffer, like we had it previously. That may be particularly bad when handling a resize event.

NAS2D/StateManager.cpp

@@ -68,6 +68,8 @@ void StateManager::setState(State* state)
  */
 bool StateManager::update()
 {
+	Utility<EventHandler>::get().pump();
+
 	if (mActiveState)
 	{
 		State* nextState = mActiveState->update();
@@ -80,8 +82,6 @@ bool StateManager::update()
 		{
 			setState(nextState);
 		}
-
-		Utility<EventHandler>::get().pump();
 	}
 	else
 	{