New Music Disc "Sulfur Echo" and unique Jukebox interaction

Add a new "Sulfur Echo" music disc. Unique mechanic: this disc can ONLY be played if a Sulfur Cube is "holding" a Jukebox inside its body. If a player inserts the disc into a Cube that has a Jukebox, the Cube starts dancing, emits note particles, and the music plays directly from the mob! This would be the first "mobile music player" in Minecraft and a very fun secret for the Chaos Cubed update.