Update new token urls (#174)

Author: chingor13

oauth2_http/java/com/google/auth/oauth2/OAuth2Utils.java

@@ -61,8 +61,8 @@
 class OAuth2Utils {
   static final String SIGNATURE_ALGORITHM = "SHA256withRSA";
 
-  static final URI TOKEN_SERVER_URI = URI.create("https://accounts.google.com/o/oauth2/token");
-  static final URI TOKEN_REVOKE_URI = URI.create("https://accounts.google.com/o/oauth2/revoke");
+  static final URI TOKEN_SERVER_URI = URI.create("https://oauth2.googleapis.com/token");
+  static final URI TOKEN_REVOKE_URI = URI.create("https://oauth2.googleapis.com/revoke");
   static final URI USER_AUTH_URI = URI.create("https://accounts.google.com/o/oauth2/auth");
 
   static final HttpTransport HTTP_TRANSPORT = new NetHttpTransport();