Added a constructor without arguments to ServiceStepMessage.

Renamed GetServiceDuration to GetServiceStepsDuration.
GetProductStepDuration now saved the serviceSteps on the blackboard instead of GetServiceDuration (now GetServiceStepsDuration).
Merge branch 'development' of https://github.com/hesselmeulenbeld/HUniversal-Production-Utrecht into development

Conflicts:
	src/java/rexos/mas/service_agent/behaviour/GetProductStepDuration.java
	src/java/rexos/mas/service_agent/behaviour/GetServiceStepsDuration.java
Renamed package rexos.mas.service_agent.behaviour to rexos.mas.service_agent.behaviours.

And the GetPartsInfoResponse behaviour sorts the serviceSteps again before passing them to the service for updating.