Add bundle size analyser.

rollup.config.js

@@ -1,7 +1,6 @@
 import typescript from 'rollup-plugin-typescript2';
 import commonjs from '@rollup/plugin-commonjs';
 import nodeResolve from '@rollup/plugin-node-resolve';
-import babel from '@rollup/plugin-babel';
 import { terser } from 'rollup-plugin-terser';
 import serve from 'rollup-plugin-serve';
 import json from '@rollup/plugin-json';
@@ -9,6 +8,7 @@ import styles from 'rollup-plugin-styles';
 import image from '@rollup/plugin-image';
 import replace from '@rollup/plugin-replace';
 import gitInfo from 'rollup-plugin-git-info';
+import { visualizer } from "rollup-plugin-visualizer";
 
 const watch = process.env.ROLLUP_WATCH === 'true' || process.env.ROLLUP_WATCH === '1';
 const dev = watch || process.env.DEV === 'true' || process.env.DEV === '1';
@@ -49,10 +49,6 @@ const plugins = [
   }),
   typescript(),
   json({ exclude: 'package.json' }),
-  babel({
-    babelHelpers: 'bundled',
-    exclude: 'node_modules/**',
-  }),
   replace({
     preventAssignment: true,
     values: {
@@ -61,6 +57,7 @@ const plugins = [
   }),
   watch && serve(serveopts),
   !dev && terser(),
+  visualizer(),
 ];
 
 /**