docs: Added information to run the quickstart sample (#1460)

samples/drive/README.md

@@ -1,6 +1,6 @@
 # Drive v3 API Samples
 
-This samples allows you to download a single file from Google Drive.
+These samples allow you to list, download, and upload files from Google Drive.
 
 ## Running the samples
 
@@ -10,8 +10,23 @@ Set the following values in `oauth2.keys.json` (up one directory):
 * `project_id`
 * `client_secret`
 
+__Run the `quickstart.js` sample:__
+
+This sample will list the files in the user's Google Drive.
+
+You'll need to do the following before you can run this sample:
+
+* Enable the [Google Drive API](https://console.developers.google.com/apis/api/drive.googleapis.com/overview).
+* Set the redirect API in the Google Cloud Console application registration to `http://localhost:3000/oauth2callback`.
+
+```
+node quickstart.js
+```
+
 __Run the `download.js` sample:__
 
+Run the `quickstart.js` sample to get a list of files in your Google Drive.  
+
 ```
 node download.js <fileId>
 ```