Add bundling down to es5 support for older browsers

.babelrc

@@ -1,6 +1,12 @@
 {
     "presets": [
-      "stage-2",
-      "react"
+      [
+        "es2015",
+        {
+            "modules": false
+        }
+    ],
+    "react",
+    "stage-0"
     ]
 }

package.json

@@ -36,8 +36,9 @@
     "babel-eslint": "^8.2.6",
     "babel-loader": "^7.1.5",
     "babel-preset-env": "^1.7.0",
+    "babel-preset-es2015": "^6.24.1",
     "babel-preset-react": "^6.24.1",
-    "babel-preset-stage-2": "^6.24.1",
+    "babel-preset-stage-0": "^6.24.1",
     "eslint": "^5.3.0",
     "eslint-config-airbnb": "^17.0.0",
     "eslint-plugin-import": "^2.13.0",

scripts/build.sh

@@ -11,7 +11,7 @@ rm -rf $build_dir
 echo "Building react-preload"
 
 echo "Transpile modules"
-$babel ./modules -d $build_dir
+$babel ./modules -d $build_dir --presets=es2015,react,stage-0
 
 echo "Create dist version for script tags"
 $webpack