[gnome-online-accounts] google: Add the Google APIs Explorer to README

[Debarshi Ray <debarshir src gnome org>]

commit f84ccb86e52bf313c8083e534099433d819dec4d
Author: Debarshi Ray <debarshir gnome org>
Date:   Thu Jan 31 17:11:05 2019 +0100

    google: Add the Google APIs Explorer to README

 README | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/README b/README
index b4e3a2aa..e7bb786a 100644
--- a/README
+++ b/README
@@ -38,6 +38,7 @@ Google
 
 OAuth 2.0:
 https://developers.google.com/accounts/docs/OAuth2InstalledApp
+https://developers.google.com/apis-explorer/
 https://developers.google.com/oauthplayground/
 
 Scopes:
@@ -50,8 +51,9 @@ https://developers.google.com/picasa-web/docs/2.0/developers_guide_protocol
 https://developers.google.com/talk/jep_extensions/oauth
 https://developers.google.com/cloud-print/docs/devguide
 
-Sometimes the documentation does not mention the OAuth2 scopes that need to be
-specified in the source code. In such cases, the following can be useful:
+Sometimes the documentation is lacking. In such cases, the following can be
+useful:
+https://developers.google.com/apis-explorer/
 https://developers.google.com/oauthplayground/
 https://discovery-check.appspot.com/