OpenBFDD todo:

 * Support Demand Mode.
 * Support Echo Mode. 
 * Support Authentication
 * The communication ports 957 and 958 should be configurable.
 * Handle signals. Currently the app will exit on many common signals.
 * We need  a way to query the settings for the 'new' session using bfdd-control.
 * Optionaly log bfdd-command message replies to bfdd-beacon log.
