Fixed issue with InvokeNow failing if trying to execute the RetryNowContinuation since the pipeline wasn't set on the ContinuationContext
Fixed a race condition in the test code that caused intermittent test failures
Added ExternalNode to represent other endpoints communicating with the system under test.
Added sample ST project to demonstrate external nodes
Added a couple sample tests for external nodes
Added another sample test

Demonstrates sending from the system under test to an ExternalNode.  Removed the need to hard-code the URI between the actual SUT and the ExternalNodes, but it needs to be baked in.
Added syncing between in-memory channel URIs when testing
Removed unused code from ExternalNode
Merge pull request #172 from RyanHauert/invoke-now-bugfix

InvokeNow() bugfix
Merge pull request #173 from DarthFubuMVC/externalNodes

External nodes