Added Song Inscription blocks

Placeholder texture
Added playback for Scarecrow's Song
Added song pillar world gen

- Added song pillars to world generation
- Improved efficiency of jar generation
- Created new 'WorldGen' section in config
- Added several config options for song pillar gen
- Moved ceramic jar gen options to 'WorldGen' section
Added new mob

+ Added Darknut and Black Knight
+ Added Heavy Broadsword + broken version
+ Changed Earth Temple boss to Black Knight
+ Modified Earth Temple decorations