Changes

• After messing around with the mod for a while, I realized I had goofed up a recipe. I ended up fixing it by getting rid of that recipe; my mod doesn't require strings to craft wool when there's already one available in the base game.
• I added two advancements: one for gathering the three discs I added to the mod and another for collecting all the discs from the base game.
• I threw in a couple of 2x2 paintings just for kicks.
• I repaired my music discs because they weren't fading out like the original ones. I realized I forgot to set the audio to mono, whoops.
• Finally, I tweaked the name tag recipe so it functions like the new one Mojang introduced, but it only uses the iron nugget.