Major Refactor: separate project into multiple crates

raidillon_ecs/src/lib.rs

@@ -0,0 +1,17 @@
+use glam::{Mat4, Quat, Vec3};
+
+#[derive(Copy, Clone)]
+pub struct Transform {
+    pub translation: Vec3,
+    pub rotation:    Quat,
+    pub scale:       Vec3,
+}
+
+impl Transform {
+    pub fn matrix(&self) -> Mat4 {
+        Mat4::from_scale_rotation_translation(self.scale, self.rotation, self.translation)
+    }
+}
+
+#[derive(Clone)]
+pub struct ModelHandle(pub usize);