RFR: 8325168: JShell should support Markdown comments [v4]

[Jan Lahoda]

> This is an attempt to add Markdown support in documentation comments to JShell.
> 
> It works by converting the Markdown text to HTML during the process of resolving `{@inheritDoc}` tags.

Jan Lahoda has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 116 commits:

 - Merge remote-tracking branch 'origin/JDK-8332858' into JDK-8298405
 - Fixing handling of synthetic/rewritten links.
 - Merge remote-tracking branch 'origin/JDK-8332858' into JDK-8298405
 - Fixing test.
 - Merge branch 'master' into JDK-8298405
 - Merge branch '8298405.doclet-markdown-v3' into JDK-8298405
 - address review feedback
 - update tests for dangling doc comments, per review feedback
 - Merge remote-tracking branch 'upstream/master' into 8298405.doclet-markdown-v3
 - Merge remote-tracking branch 'upstream/master' into 8298405.doclet-markdown-v3 # Please enter a commit message to explain why this merge is necessary, # especially if it merges an updated upstream into a topic branch. # # Lines starting with '#' will be ignored, and an empty message aborts # the commit.
 - ... and 106 more: https://git.openjdk.org/jdk/compare/b75f896f...4b02060d

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Changes: https://git.openjdk.org/jdk/pull/17686/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17686&range=03
  Stats: 2036 lines in 9 files changed: 1189 ins; 842 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/17686.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17686/head:pull/17686

PR: https://git.openjdk.org/jdk/pull/17686