Added StreamMaster status information
Created by: michele-brambilla
StreamMaster exposes a queue which contains informations on its status and on each streamer:
- StreamMaster stopped, running or "has finished"
- for each Streamer number of messages, errors and byte received
- for each Streamer average message size and frequency (plus rms)
The StreamMaster status can be converted in a rapidJSON Document (or printed on the screen for debugging)
Closes #26 (closed) Closes #28 (closed)