Update -- SAGE Demo

This is the SAGE 2022 demo of Sonic the Hedgehog TX, and it does a number of things:

• The game is now styled after Sonic Pocket Adventure, with new sprites for Cream
• Added a Spin Dash to Sonic
• Made Cream unlockable
• Re-added the drowning music
• Added invincibility boxes
• Tweaked the level design in Spring Breeze 2
• Made the Spring Breeze boss harder
• Fixed a bug with animations
• Fixed a bug with semi-solid platforms
• Removed loops
• The game now ends after Industrial Grave 1