C2MS13 — Change Figure 6-1 Message Field Multiplicity

Figure 6-1 Message Field Multiplicity should be redone. It uses the Log Message, but has incomplete constraints, and some of the fields in Log Message are deprecated, so it's not a great example. Consider Event Message instead.

Additionally, I can't find a diagram in the model that was used to create this, so a specific diagram, including the note, should be created in the model as well for consistency when the given example message might change in the future.