[Nestmates] Draft core reflection API

[Brian Goetz]

The specs are fine. But a reader who doesn't know what a nest is will never figure it out from the docs.  Would be good if nest host had an API note that explained how classes become nestmantes.  

Sent from my MacBook Wheel

> On Nov 7, 2017, at 7:26 AM, David Holmes <david.holmes at oracle.com> wrote:
> 
> For comment:
> 
> http://cr.openjdk.java.net/~dholmes/8188075/webrev/raw_files/new/java/lang/Class.html#getNestHost()
> 
> Three functions added:
> - getNestHost
> - isNestmateOf
> - getNestMembers
> 
> The first two never throw exceptions related to nest hosts or nest membership. The third does.
> 
> Thanks,
> David