Rename crate folders to remove raidillon prefix

assets/src/model_manager.rs

@@ -0,0 +1,14 @@
+use std::cell::RefCell;
+use std::path::Path;
+use std::rc::Rc;
+
+pub type ModelManagerRef = Rc<RefCell<Box<dyn ModelManager>>>;
+
+
+/// The asset manager trait of Raidillon.
+pub trait ModelManager {
+    /// Loads a gltf model to VRAM.
+    fn load_gltf(&mut self, path: &Path);
+    /// Unloads the loaded model from VRAM.
+    fn unload_model(&mut self, path: &Path);
+}