Use es2015 preset rather than cherry picking transform plugins

Could prevent accidentally reducing browser compat in the future.

package.json

@@ -14,9 +14,15 @@
     "prepublish": "npm run build"
   },
   "babel": {
+    "presets": [
+      [
+        "es2015",
+        {
+          "modules": false
+        }
+      ]
+    ],
     "plugins": [
-      "transform-es2015-arrow-functions",
-      "transform-es2015-block-scoping",
       "array-includes"
     ]
   },
@@ -53,8 +59,7 @@
   "devDependencies": {
     "ava": "^0.17.0",
     "babel-plugin-array-includes": "^2.0.3",
-    "babel-plugin-transform-es2015-arrow-functions": "^6.22.0",
-    "babel-plugin-transform-es2015-block-scoping": "^6.24.1",
+    "babel-preset-es2015": "^6.24.1",
     "browser-env": "^2.0.23",
     "camelcase": "^4.0.0",
     "coveralls": "^2.11.15",