RFR: JDK-8295756 Improve NonLocalRegistry Manual Test Process [v6]

[Bill Huang]

> The current non local registry tests require a manual process that runs rmiregitrty on a different machine and changes the -Dregistry.host property in the source before running the tests on the local machine. This task is created to improve this manual process and provide a clearer instruction to the test engineer about the test requirement. 
> 
> Tests include: 
> java/rmi/registry/nonLocalRegistry/NonLocalSkeletonTest.java 
> java/rmi/registry/nonLocalRegistry/NonLocalRegistryTest.java 
> javax/management/remote/nonLocalAccess/NonLocalJMXRemoteTest.java

Bill Huang has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains seven commits:

 - Merge master
 - Implemented review comments.
 - Implemented review comments.
 - Reverted exclusion of nonlocal registry tests.
 - Updated test instruction messages.
 - Updated TEST.groups
 - JDK-8295756 Improve NonLocalRegistry Manual Test Process

-------------

Changes: https://git.openjdk.org/jdk/pull/10825/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10825&range=05
  Stats: 350 lines in 7 files changed: 256 ins; 58 del; 36 mod
  Patch: https://git.openjdk.org/jdk/pull/10825.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10825/head:pull/10825

PR: https://git.openjdk.org/jdk/pull/10825