Refactored the WHOLE project

From a simple test file, we're now on road to create a real project
Took 3 hours, but code looks nice

src/utils/animateMesh.js

@@ -0,0 +1,28 @@
+import * as THREE from 'three';
+
+const ANIMATION_SPEED_MULTIPLIER = 1.4;
+let mixersToUpdateEachFrame = [];
+
+export function addAnimationMixerOnMesh(mesh, actions){
+    //See https://threejs.org/docs/#manual/en/introduction/Animation-system
+    /*Function used to add an animationMixer on a mesh, so we can easily start or stop animations
+      Takes the animated mesh, and a list of actions names that should become animated */
+
+    const mixer = new THREE.AnimationMixer(mesh.scene);//We create a new mixer to manage every animations on this mesh
+
+    mesh.animationMixer = mixer;//We add this mixer on the mesh
+    mesh.animationActions = {};//And create an object that will hold actions
+    
+    actions.forEach(element => {
+        const clip = THREE.AnimationClip.findByName( mesh.animations, element );//For each given action name, we get a clip
+        mesh.animationActions[element] = mixer.clipAction(clip);//and save it as an action
+    });
+
+    mixersToUpdateEachFrame.push(mixer);
+}
+
+export function updateAnimations(deltaSeconds){
+    mixersToUpdateEachFrame.forEach(element => {
+        element.update(deltaSeconds * ANIMATION_SPEED_MULTIPLIER);
+    });
+};