Sheetmetal Planes

This is a tiny mod that adds all blocks under the forge:sheetmetals tag to the list of materials for [Simple Planes](https://modrinth.com/mod/simple-planes). This includes decorative sheetmetal materials from popular tech mods like Immersive Engineering. This mod does not add its own sheetmetal blocks, it only lets you use sheetmetal blocks from other mods to build planes.