Test driver for client
Fix bug when calling plug.handler() ('task' referenced before assignment)
Reorder statements
Commands sent to client
Big update. File transfer is now working.
zmq sockets
Bilateral connection between client and server
The client respond to read_chunk & write_chunk
Notifier on client
Few bugs: - doesn't truc file when the new file has a size lesser than the old one
          - Double-write the file on updates
Fix bug when calling plug.handler() ('task' referenced before assignment)
Merge branch 'test_client' into develop

Conflicts:
	entries.json
	onitu.ini
	onitu/api/metadata.py
	onitu/api/plug.py
	onitu/referee/referee.py