New unit tests; better plugin initialization; fixed reply of messages not routed to plugins. 

- Updated path monitor to skip initial notification.
- Simplified transport package path from file name logic.
- Inject inbound transport into received requests.
- Use injected inbound transport name to reply to requests that could not be routed to a plugin.
- Add support for @initializer and call after plugin loading.  This gives the plugin a proper opportunity to initialize properties such as *uuid* as needed.
- Simplified PathMonitor code.