Check for PDO MySQL extention not just PDO
Check for PDO MySQL extention not just PDO

Change to check for pdo_mysql as test would pass if PDO was installed
but not the PDO MySQL extension

avdevs/concrete5,MichaelMaar/concrete5,TimDix/concrete5,MichaelMaar/concrete5,avdevs/concrete5,TimDix/concrete5,matt9mg/concrete5,avdevs/concrete5,MichaelMaar/concrete5,matt9mg/concrete5,TimDix/concrete5,matt9mg/concrete5