Import and export improved

- Import paths are now vname and not sym
- Imports and exports accept multiple space-delimited operators in []

as a result, we can now reliably import and export the operator *

- error reporting ergonomics

src/systems/stl/stl_system.rs

@@ -41,7 +41,7 @@ impl IntoSystem<'static> for StlConfig {
       constants: HashMap::from([(i.i("std"), fns)]),
       code: embed_to_map::<StlEmbed>(".orc", i),
       prelude: vec![FileEntry::Import(vec![Import {
-        path: i.i(&[i.i("std"), i.i("prelude")][..]),
+        path: vec![i.i("std"), i.i("prelude")],
         name: None,
       }])],
       handlers: HandlerTable::new(),