RFE ThreadGroup.root suggestion

[David Holmes]

It might be useful to have either VMThread or VMSystem define
getRootThreadgroup() and then have Threadgroup do:

static ThreadGroup root = VMxxx.getRootThreadgroup();

This would allow the root threadgroup to be a VM specific subclass of
ThreadGroup if desired.

I would use this to define a special root threadgroup class for a real-time
JVM that overrides uncaughtException to be more aware of memory-management
issues.

Cheers,
David Holmes