consolidated VM notes for primitive classes

[Brian Goetz]

I also lightly updated the 01- and 02- documents based on recent 
discussions.

On 4/21/2021 2:51 AM, John Rose wrote:
> Brian and I hammered out a document this week that
> captures what we think is emerging as our shared
> understanding of how adapt the JVM to support
> primitive classes.
>
> It is still white-hot, not even off the press, but I think
> it is worth looking it even in its unfinished state.
>
> https://github.com/openjdk/valhalla-docs/blob/main/site/design-notes/state-of-valhalla/03-vm-model.md 
> <https://github.com/openjdk/valhalla-docs/blob/main/site/design-notes/state-of-valhalla/03-vm-model.md>
>
> That is the JVM side, only.  Most of it is already
> prototyped in HotSpot, some is not.
>
> I’ll let Brian speak for the valhalla-doc repository
> as a whole, but I wanted to get this out there for
> tomorrow’s meeting.
>
> — John