Var: redesign of how we handle generic value passing

[tap]

• In Jamoma1 the TTValue is internally a std::vector, and thus always alloced on the heap.
• In Jamoma2 thus far the Value is alloc'd on the stack if it is 8-bytes or less (good) or on the heap otherwise (could be good or bad but it increases the complexity).

Also, Jamoma1 TTValue can have N elements whereas thus far the Jamoma2 Value can have only 1 element -- but we need to be able to pass collections of generic elements in Jamoma2 as well.

Ideally we could do as much of this as possible with constexpr so we are wasting cpu cycles getting values out of vectors or disambiguating whether we have a vector or a value etc.

[tap]

This is more or less done, but I feel like we need to write an article about it. Or maybe some more narrative form of documentation / discussion.

I'm not sure what the best way is to set that up with Doxygen. I think @nwolek set up something like that for Jamoma1 code tutorials?

[nwolek]

Looks like you are referring to these: https://github.com/jamoma/Jamoma/tree/master/Doxygen/intro_chapters

They show up in order. I intentionally numbered those with 10s so that we could squeeze additional topics between them when necessary.

Any chapters that are added there will automatically become part of the api.jamoma.org site. If you want to set up a different Doxygen-generated site for jamoma2, we could do that.

And if you want "just write" and then hand stuff off to me for formatting, that can work too.