Added several new .ogg files such as:

• yakusoku.ogg
• wet_hands.ogg
• watcher.ogg
• sweden.ogg
• subwoofer_lullaby.ogg
• puzzlebox.ogg
• pokopoko.ogg
• oxygene.ogg
• minecraft.ogg
• mice_on_venus.ogg
• living_mice.ogg
• komorebi.ogg
• key.ogg
• haggstrom.ogg
• featherfall.ogg
• dry_hands.ogg
• eld_unknown.ogg
• danny.ogg
• deeper.ogg
• clark.ogg
• ballad_of_the_cats.ogg
• concrete_halls.ogg
• dead_voxel.ogg
• warmth.ogg
• aria_math.ogg
• biome_fest.ogg
• blind_spots.ogg
• dreiton.ogg
• haunt_muskie.ogg
• taswell.ogg
• the_end.ogg
• alpha.ogg

As of 1.21 the game now uses named files in place of music instead of the old naming like nuance1-4 or piano1-3 etc. so they got renamed to .ogg_old file extension since they're unused now.