Add ends compartment on ConnectionDef and AllocationDef graphical nodes #1945
Description
Create an ends compartment (list compartment) for ConnectionDefinition nodes.
Update the tool creating an ConnectionDefinition. It must now creates two "end refs" in addition to the ConnectionDefinition.
Add a tool on ConnectionDefinition nodes allowing to create ReferenceUsages.
This must work on ConnectionDefinition nodes and on the ends compartment itself.
As always, check in the SysMLv2 specification what are the consequences of the creation of such elements (elements to create, properties to set, implicit relations)