BACM12 — Semantics of reified relations should be aggregation

The BACM 1.1b1 document does not explicitly state that the semantics of all reified relations is aggregation, leading to a possible interpretation of these relationships as ownership or specialization. The BACM 1.1b1 document explicitly provides simple relations of specialization, composition and aggregation. All simple associations and all stereotyped associations should be interpreted as aggregations only.

Change 7.2 to clarify aggregational semantics of reified and non-reified relations

Change text in sections 7.2.1.2, 7.2.1.3 and 7.2.1.4 to explain that these relations have the semantics of aggregation and should not be interpreted as composition or specialization.