SLING-4068 : Drop support PROPERTY_NOTIFICATION_JOB event property
SLING-4065 : Add notification when a job is added
SLING-4063 : Fix job queue statistics

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1632253 13f79535-47bb-0310-9956-ffa450edef68