Bar graph added.

node_modules/d3-force/src/index.js

@@ -0,0 +1,8 @@
+export {default as forceCenter} from "./center";
+export {default as forceCollide} from "./collide";
+export {default as forceLink} from "./link";
+export {default as forceManyBody} from "./manyBody";
+export {default as forceRadial} from "./radial";
+export {default as forceSimulation} from "./simulation";
+export {default as forceX} from "./x";
+export {default as forceY} from "./y";