Changed the broker address (in the windows configuration) to use a more generic configuration option
Moved some variables which reflect the global state of execution (more than that of a particular `Listener`) to the `State` class
Refactored the execution of the prediction process to occur on a background thread
Refactored the handling of `metrics_to_predict` and `start_forecasting.exponentialsmoothing` events
Introduced support for `stop_forecasting.exponentialsmoothing`events