googleapis: Updated readme template

resources/README.md

-# Package of Google APIs
+Auto-generated Dart libraries for accessing [Google APIs][libs].
 
-## Description
-
-This repository contains auto-generated client libraries for accessing 
-Google APIs using dart. It has the usual dart package layout.
-
 ## Usage
 
-The first step is to obtain oauth2 access credentials. This can be done using
-the `googleapis_auth` package. Your application can access APIs on behalf of a
+First, obtain OAuth 2.0 access credentials. This can be done using the
+`googleapis_auth` package. Your application can access APIs on behalf of a
 user or using a service account.
 
 After obtaining credentials, an API from the `googleapis` package can be
 accessed with an authenticated HTTP client.
 
-The following is an example of a command line application which lists files
-in Google Drive by using a service account. 
+## Example
+
+The following command line application lists files in Google Drive by using a
+service account.
 
 Create a `pubspec.yaml` file with the `googleapis_auth` and `googleapis`
 dependencies.
 
-    ...
-    dependencies:
-      googleapis: any
-      googleapis_auth: any
+```yaml
+...
+dependencies:
+  googleapis: any
+  googleapis_auth: any
+```
 
 Create a service account in the Google Cloud Console and save the credential
-information. After that the Cloud Storage API can be accessed like this:
+information.
 
-    import 'package:googleapis/storage/v1.dart';
-    import 'package:googleapis_auth/auth_io.dart';
+Then create a Dart application to list files in a spececific project. *In the
+example below, files from the `dart-on-cloud` project are listed.*
 
-    final Credentials = new ServiceAccountCredentials.fromJson(r'''
-    {
-      "private_key_id": ...,
-      "private_key": ...,
-      "client_email": ...,
-      "client_id": ...,
-      "type": "service_account"
-    }
-    ''');
+```dart
+// bin/list_files.dart
 
-    void main() {
-      clientViaServiceAccount(Credentials,
-                              [StorageApi.DevstorageReadOnlyScope]).then((http) {
-        var storage = new StorageApi(http);
-        storage.buckets.list('dart-on-cloud').then((buckets) {
-          print("Received ${buckets.items.length} bucket names:");
-          for (var file in buckets.items) {
-            print(file.name);
-          }
-        });
-      });
-    }
+import 'package:googleapis/storage/v1.dart';
+import 'package:googleapis_auth/auth_io.dart';
+
+final _credentials = new ServiceAccountCredentials.fromJson(r'''
+{
+  "private_key_id": ...,
+  "private_key": ...,
+  "client_email": ...,
+  "client_id": ...,
+  "type": "service_account"
+}
+''');
+
+const _SCOPES = const [StorageApi.DevstorageReadOnlyScope];
+
+void main() {
+  clientViaServiceAccount(_credentials, _SCOPES).then((http_client) {
+    var storage = new StorageApi(http_client);
+    storage.buckets.list('dart-on-cloud').then((buckets) {
+      print("Received ${buckets.items.length} bucket names:");
+      for (var file in buckets.items) {
+        print(file.name);
+      }
+    });
+  });
+}
+```
+
+[libs]: https://developers.google.com/discovery/libraries/