RFR: 8301302: Platform preferences API [v10]

[Michael Strauß]

> Please read [this document](https://gist.github.com/mstr2/9f46f92c98d3c86aa6a0b4224a9a6548) for an introduction to the Platform Preferences API, and how it interacts with the proposed style theme and stage appearance features.

Michael Strauß 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 18 additional commits since the last revision:

 - Merge branch 'master' into feature/platform-preferences
 - Format arrays in test application
 - Suppress empty change message in test application
 - Update Eclipse .classpath file
 - improve javadoc
 - Added javadoc link to list of platform preferences
 - Revert Application changes
 - Addressed review comments
 - Removed application preferences implementation
 - Added test
 - ... and 8 more: https://git.openjdk.org/jfx/compare/e6b6074c...2837e33c

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

Changes:
  - all: https://git.openjdk.org/jfx/pull/1014/files
  - new: https://git.openjdk.org/jfx/pull/1014/files/4172fa61..2837e33c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1014&range=09
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1014&range=08-09

  Stats: 385585 lines in 6288 files changed: 217555 ins; 124574 del; 43456 mod
  Patch: https://git.openjdk.org/jfx/pull/1014.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1014/head:pull/1014

PR: https://git.openjdk.org/jfx/pull/1014