RFR: JDK-8285764: Add system property for Java SE specification maintenance version [v2]

[Joe Darcy]

> Add a new system property, java.specification.maintenance.version, to return the maintenance release number of the Java SE specification being implemented. The property is unset, optional in the terminology of System.getProperties, for an initial release of a specification.
> 
> Please also review the CSR https://bugs.openjdk.java.net/browse/JDK-8285764
> 
> I'll update copyright years before an integration.

Joe Darcy has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains five additional commits since the last revision:

 - Respond to review feedback.
 - Respond to CSR feedback.
 - Merge branch 'master' into JDK-8285497
 - Update comment in template.
 - JDK-8285497: Add system property for Java SE specification maintenance version

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8437/files
  - new: https://git.openjdk.java.net/jdk/pull/8437/files/4ea4708b..101ad872

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8437&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8437&range=00-01

  Stats: 670 lines in 38 files changed: 614 ins; 8 del; 48 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8437.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8437/head:pull/8437

PR: https://git.openjdk.java.net/jdk/pull/8437