[Feature]: Handle Composite Aggregation correctly #75

What type of issue is this?

• Bug report
• Feature request

Prerequisites

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Description

SysML2 defines 2 composite Aggregation that are not-derived.

The Section 7.2 describing the ownership of element can be resumed like:

If Element B is owned by Element A, the structure looks like this:

• Element A holds a reference in its OwnedRelationship list to Relationship R.
• Relationship R points back to Element A via its OwningRelatedElement property.
• Relationship R holds a reference in its OwnedRelatedElement list to Element B.
• Element B points back to Relationship R via its OwningRelationship property.

Proposed solution: Implements a specific collection to replace the List used when dealing with Composite aggregaiton to reflect this pattern

Steps to Reproduce

System Configuration

• SysML2.NET version:
• Environment (Operating system, version and so on):
• .NET Framework version:
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