C2MS11 — Find a Reusable Way to Represent types like Mnemoic, Sample, Others in Model

There are many 'classes' in the model (because that's what is in the message) for Mnemonic, frequently with different values. Same probably true of Sample and others. It would be great if these structs in the messages and classes in the model were better reused so that we don't have two different items both called "Mnemonic".

This issue sort of harkens back to when we had things like "Required Fields" in each message in the model, with no relationship to each other.