add functions in TopologyManager to prepare and launch actors
pass path argument to TransactionLogger
add LogReplayer actor
remove MboxProducer, add sendMsg() to Mbox
start Listener
Listener is implemented
have Listener update topology based on version of atomic integer, which should be updated when topology changes. Listener doesn't read its mbox, so it can't be told about topology updates.
do topology update based on atomic version
IbGateway implemented
ObGateway
Merged mtravis.
Began implementation of configuration handler in the native code.