QPIDJMS-9: update JMSExpiration to use absolute-expiry-time or 'current time + TTL' and NOT 'creation-time + ttl' as this would incorrectly lead to an earlier-than-desired JMSExpiration value because the TTL field is mutable during transit and creation-time is not.

git-svn-id: https://svn.apache.org/repos/asf/qpid/jms/trunk@1550139 13f79535-47bb-0310-9956-ffa450edef68