Updated stocks example README (#12634)

examples/flutter_gallery/README.md

@@ -7,7 +7,7 @@ Demo app for the material design widgets and other features provided by Flutter.
 You can follow these instructions to build the gallery app
 and install it onto your device.
 
-### Prereqs
+### Prerequisites
 
 If you are new to Flutter, please first follow
 the [Flutter Setup](https://flutter.io/setup/) guide.

examples/stocks/README.md

+# Stocks
+
+Demo app for the material design widgets and other features provided by Flutter.
+
+## Building
+
+You can follow these instructions to build the stocks app
+and install it onto your device.
+
+### Prerequisites
+
+If you are new to Flutter, please first follow
+the [Flutter Setup](https://flutter.io/setup/) guide.
+
+### Building and installing the stocks demo app
+
+* `cd $FLUTTER_ROOT/examples/stocks`
+* `flutter upgrade`
+* `flutter run --release`
+
+The `flutter run --release` command both builds and installs the Flutter app.
+
+## Interationalization
+
+This app has been internationalized (just enough to show how it's
+done). It's an example of how one can do so with the
+[Dart intl package](https://pub.dartlang.org/packages/intl).
+
+The [Flutter Internationalization Tutorial](https://flutter.io/tutorials/internationalization/)
+covers Flutter app internationalization in general.
+
+See [regenerate.md](lib/i18n/regenerate.md) for an explanation
+of how the Dart interationalization tools, like
+`intl_translation:generate_from_arb`, were used to generate
+localizations for this app.
+
 ## Icon
 
 Icon was created using Android Asset Studio:
@@ -6,4 +42,3 @@ https://romannurik.github.io/AndroidAssetStudio/icons-launcher.html#foreground.t
 From this clipart:
 https://openclipart.org/detail/30403/tango-go-up
 Which is public domain.
-