[ipv6] Issue Tracking

[Chris Hegarty]

Arthur, others,

In order to help track the all the IPv6 related work, we have the
following issues:

Improved IPv6 Support ( for implementation issues )
   https://bugs.openjdk.java.net/browse/JDK-8221681

Update JDK networking tests for IPv6-only environments ( test-only )
   https://bugs.openjdk.java.net/browse/JDK-8220499

We can use these "umbrella" issues to keep track of the individual
bugs and fixes, which can be either sub-tasks or linked-issues. Keeping
a reasonably clean separation between test-only changes and
"real" implementation changes should help with tracking ( since there
will be likely a number of pushes/fixes that provide incremental
improvements ).

Again, for discussion, at least on net-dev, lets use the `[ipv6]`
prefix in the subject line.

Regards,
-Chris.