Audio updates and more! — Atomcraft Steam update #638422

This update adds some more sounds for different sorts of materials, as well as audio leveling - now the default for all audio levels is halfway across the settings bar, and the default audio levels should be much more reasonable. :)Ethanol can burn now (very quickly)!Also a lot of other details:CONTENT: materials can now play sand, metal, or rock sound sets when settlingCONTENT: made Ethanol flammable and added vapor phaseCONTENT: added a reaction between Lithium Manganese Oxide and Sulfuric Acid to get us out of a material dead endQuality-of-Life: show the last-played date/time on the World buttons in the Select World screenMUSIC: added a track to the surface biome music rotation, and added a system to make the game pick fewer recently-heard tracksBUGFIX: prevented combustion from allowing products to escape through sealed diagonalsBUGFIX: some materials would incorrectly show their sou...