Fixes the splash screen so that it displays until the game has actually done initial setup and can display GUI elements. This prevents the ugly blank window just sitting there while the GUI loads.

Engine/source/platform/platform.h

@@ -338,6 +338,9 @@ namespace Platform
    // display Splash Window
    bool displaySplashWindow( String path );
 
+   // close Splash Window
+   bool closeSplashWindow();
+
    void openFolder( const char* path );
 
    // Open file at the OS level, according to registered file-types.