Issue #86: Minor error - Inconsistent use of parent/child and parent-child in EA diagrams

I am currently going through the diagrams in Sparx EA for CSPA LIM and checking them for model coherence (Design Principle 11)

Sometimes we use parent/child and sometimes we use parent-child.

I suggest we change the two occurences of parent/child in the Referential MetadataGroup Diagram and in the Universe-Population-Concept-Unit Type Diagram to parent-child