SYSML17 — Added BehavioralFeatures to AdjuctProperty

Add UML::BehavioralFeature (UML::Operation or UML::SignalReception) to the allowed list of UML metaclasses of SysML::AdjunctProperty.principal, thus allowing a visual symbol (association) as well as fUML implementable way of accessing runtime instances of these behaviors through the structures that have them as their context. You could add them to the same constraint as CallAction, using the UML::BehavioralFeature.method as the constraining metaproperty . Also add an “or” to the constraint to allow SignalReception to get to it’s Signal metaproperty instead, or just create a new constraint separate for SignalReceptions.