nuclear fog and more

Added:
*Potato battery block
**Low-tier energy storage with 10k HE
*Privet rocket
**Small nuclear 84mm rocket for carl gustav
*Nuclear fog
**Cloud particles that spawn in high-radiation chunks
**Spawn frequency and radiation threshold are configurable
*More config options
**Speed of mk4 explosions
**Speed of fallout spread
**Fallout thunderstorm (fallout can now cause thunderstorms)
**Fallout thunderstorm radiation (thunderstorms can be radioactive!)

Changed:
*Lowered radiation levels from nuclear explosions
*Updated all battery block textures with sprites so thoughtfully provided by our overlord Hoboy
*Config has been updated and regrouped, please delete the file before using this version!

Fixed:
*Removed more logspam
*Fixed savedatas having null worlds which can crash under very specific circustances