* fixed frame gaps when exiting a cutscene. This must be properly synchronized with the state handler in the main loop.
* reactivated the loading screens. With texture precaching working the delay when loading a map becomes significant enough to require a visual feedback.
* RR does not play 'bonusmusic' on its summary screen.
It will no longer depend on the game state when the menu was opened but the current game state - only on the dedicated menu screen there's no dimming - everywhere else a dim gets applied.
Also renamed GS_DEMOSCREEN to GS_MENUSCREEN for clarity