Validate OnBehalfOfCompID(115) and DeliverToCompID(128)

OnBehalfOfCompID(115) and DeliverToCompID(128) tags are used in some FIX Drop messaging to indicate the party, whose message was delivered to the third party receiving drop copy flow.

Configure SBT to run tests written in JUnit. Also, fix broken tests in RecvAppOrAdminMsgSpec and SendHeartbeatSpec tests. Make JUnit verbose when running tests under SBT's as the tests take suspiciously long time to complete.

Drop 'isPointToPoint' from 'Message' and 'MessageHeader' as no longer used.