PROTON-589 Interfaces to facilitate passive mode.

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/branches/rajith-messenger-passive@1602912 13f79535-47bb-0310-9956-ffa450edef68
PROTON-589
1. Removed dependency on the driver code.
2. Changed the code to use the Collector/Event interface from engine.
3. Added code to support non passive mode.

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/branches/rajith-messenger-passive@1602913 13f79535-47bb-0310-9956-ffa450edef68