puts back old veribalge for rails#4 (was rails#2) instead of

lib/webpacker/manifest.rb

@@ -109,7 +109,7 @@ def missing_file_from_manifest_error(bundle_name)
 2. Your app has code with a non-standard extension (like a `.jsx` file) but the extension is not in the `extensions` config in `config/webpacker.yml`
 3. You have set compile: false (see `config/webpacker.yml`) for this environment
    (unless you are using the `webpack -w` or the webpack-dev-server, in which case maybe you aren't running the dev server in the background?)
-4. Webpacker has not yet re-run to reflect updates.
+4. webpack has not yet re-run to reflect updates.
 5. You have misconfigured Webpacker's `config/webpacker.yml` file.
 6. Your webpack configuration is not creating a manifest.