Need system-level and soak tests to exercise Proton.

The existing system tests for QPID are, naturally, tests of a
broker-centric model. Since AMQP 1.0 allows for messaging models that
go beyond the simple broker-based approach, we need a system test bed
that can do the same. This would include support for testing
peer-to-peer patterns, as well as testing distributed messaging
systems yet to be defined.