Nestmates spec updates

[Dan Smith]

> On May 3, 2018, at 11:45 AM, Karen Kinnear <Karen.Kinnear at oracle.com> wrote:
> 
> Thank you for the updates. They look great.
> Very much appreciate the ways in which you have made the specification clearer in the process.
> 
> thanks,
> Karen

Thank Alex, BTW. This round of changes came from his review and massaging of the text to integrate it with the official JVMS.