fix for: https://issues.apache.org/jira/browse/AMQCPP-455

Makes the connection factory config data thread safe.

git-svn-id: https://svn.apache.org/repos/asf/activemq/activemq-cpp/trunk@1444160 13f79535-47bb-0310-9956-ffa450edef68
https://issues.apache.org/jira/browse/AMQCPP-457

Better control over Transport start and stop.

git-svn-id: https://svn.apache.org/repos/asf/activemq/activemq-cpp/trunk@1444161 13f79535-47bb-0310-9956-ffa450edef68