Rename sub-scope/SubScope to module.

tests/modules.rs

@@ -1,15 +1 @@
-use rhai::{EvalAltResult, Scope, SubScope, INT};
-
-#[test]
-#[cfg(not(feature = "no_import"))]
-fn test_sub_scope() {
-    let mut my_scope = Scope::new();
-
-    let mut sub_scope = SubScope::new();
-    sub_scope.insert("x".to_string(), (42 as INT).into());
-
-    my_scope.push_sub_scope("my_plugin", sub_scope);
-
-    let s = my_scope.find_sub_scope("my_plugin").unwrap();
-    assert_eq!(*s.get("x").unwrap().downcast_ref::<INT>().unwrap(), 42);
-}
+use rhai::{EvalAltResult, Scope, INT};