Modify comments, more non-functional code cleanup

src/hybridSimulation.js

@@ -108,9 +108,9 @@ export default function (sim, forceS, forceF) {
 
   function sampleEnded() {
     event.call("startInterp");
-
     simulation.stop();
     simulation.force("Sample force", null);
+    // Reset velocity of all nodes
     for (let i=sample.length-1; i>=0; i--){
       sample[i].vx=0;
       sample[i].vy=0;