upgrade

1. login to your Pantheon site via SSH 

2. cd /opt 

3. sudo tar czfv old-drush.tar.gz drush (save your old drush just in case) 

4. sudo rm -rf drush 

5. sudo git clone --branch 7.x-4.x http://git.drupal.org/project/drush.git

4. sudo chmod 777 /opt/drush/includes 

5. http://download.pear.php.net/package/Console_Table-1.1.4.tgz

6. copy Table.php to /opt/drush/includes via SFTP

7. rename Table.php as table.inc 

7a. an alternate - and probably better - method is to git clone your "new" drush to your local, perform steps 5-7 on your local, and then commit/push the table.inc file to Pantheon