Cleans up the WASM environment handling.

Instead of passing the entire script resolver as a pointer to the WebAssemblyEnv, we now have split off the data actually relevant to the environment into it's own class, which is stored inside of an Arc.

tests/common/library_loader.rs

@@ -281,6 +281,7 @@ fn load_wasm(path: &String, library: &mut WebAssemblyScriptResolver) {
     let mut buffer = Vec::new();
     reader.read_to_end(&mut buffer).unwrap();
     library.load_wasm_from_bytes(&buffer);
+    library.finalize();
 }
 
 fn parse_form(name: StringKey, value: &Value, library: &mut StaticData) -> Form {