Add entry to select between normal and tweaked Link Force

- Tweaked link force should initialize and perform the calculation a tiny bit faster (maybe insignificant)

index.js

@@ -13,7 +13,7 @@ export { default as forceBarnesHut}
 export { default as tSNE}
   from "./src/t-sne";
 
-export { default as forceLinkOptimized}
+export { default as forceLinkTweaked}
   from "./src/link";
 
 export { default as hybridSimulation}