wip: Changes of the week

- Move engine to a different crate
- Add engine trait
- Refactor the rest of the codebase to work with these changes
- Add debug ui buffer, use it to finish imgui support

game/src/main.rs

@@ -1,13 +1,16 @@
 use std::path::Path;
 use glam::{Quat, Vec3};
-use raidillon_core::{Engine, Scene, System};
-use raidillon_core::system::SystemContext;
+use raidillon_engine::{Engine, system::System};
+use raidillon_engine::system::SystemContext;
 use raidillon_platform::{Platform, Camera};
 use raidillon_assets::model_path;
+use raidillon_core::engine::EngineTrait;
 use raidillon_ecs::components::ModelHandle;
 use raidillon_ecs::Transform;
+use raidillon_core::scene::Scene;
 #[cfg(feature = "glium")]
 use raidillon_glium::GliumPlatform;
+use raidillon_core::DebugUIBuffer;
 
 const TEST_GLTF: &str = "pink-monkey.gltf";
 
@@ -48,6 +51,7 @@ impl System for RenderingTestSystem {
         // if let Some(mut debug_ui) = ctx.platform_context.imgui_ui.as_ref().map(|ui| ui.borrow_mut()) {
         //     debug_ui.text("Hello World!");
         // }
+        ctx.debug_ui_buffer.borrow_mut().text("Hello World!".to_owned());
     }
 }