SA for ZGC

[Yasumasa Suenaga]

Hi all,

I checked SA implementation for ZGC, but it is not yet available.
For example, we can see WrongTypeException when CLHSDB `universe`
command is executed.

As the first step, I propose to implement ZCollectedHeap and related classes for
 SA as this webrev:

  http://cr.openjdk.java.net/~ysuenaga/z/sa-universe/

After applying this patch, we can use `universe` command on CLHSDB.
(I followed `VM.info` jcmd output format)

Of course, it is not all. We need to work more for it.


Thanks,

Yasumasa