Add cutscene skipping

[pyuxiang]

Propose we abandon this: (1) cutscenes aren't that long in the first place, (2) at the moment, skipping will not fade out the background tracks -> hard cut in the music/sfx.

[ThePlasmak]

Hm I still feel like it's good to add for ease of replayability (especially if we're adding scoring)—good point on the music/SFX issue though, I didn't know about that

Probably (mentally) setting this as a very low priority atm