main_interactive.py:
 * start/stop cameras from an interactive shell
 
cam_handler_remote.py
 * entry point to camera backend

cam_manager.py
 * load the configuration
 * starts a command queue for every camera
 * submits start/stop commands to the queue
  
cam_handler_thread.py
 * maintains/starts/stops the encoding subprocesses

playlist_manager.py
 * is an observer of the cam_handler_thread and updates the master playlist

ffmpeg_cmd_builder.py
 * compose ffmpeg command
 * run ffprobe

ffmpeg_process_factory.py
 * creates process factories for later execution of the ffmpeg process

hls_playlist.py
 * maintains a list of the different versions of a single input stream
 * implements ordering by BANDWIDTH

process_factory.py
 * abstract base class

transcoding_observer.py
 * abstract base class

zmq_process.py
 * base class for all zmq implementers