RFR: 8251496: Fix doclint warnings in jdk.net.httpserver [v4]

[Patrick Concannon]

> Hi,
> 
> Could someone please review my doc-only fix for JDK-8251496 - ‘Fix doclint warnings in jdk.net.httpserver’ ?
> 
> This fix addresses the warnings generated by `javadoc -Xdoclint` due to missing/incomplete API documentation for
> several classes within `jdk.net.httpserver`.
> Kind regards,
> Patrick

Patrick Concannon 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 three additional
commits since the last revision:

 - 8251496: removed @throws IOException from HttpExchange.sendRequestHeaders; to be dealt with in separate issue
   (JDK-8253005)
 - 8251496: reworded abstract cstr comments; removed unnecessary punctuation
 - 8251496: Fix doclint warnings in jdk.net.httpserver

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/81/files
  - new: https://git.openjdk.java.net/jdk/pull/81/files/660a549c..45303d9f

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=81&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=81&range=02-03

  Stats: 557 lines in 33 files changed: 285 ins; 212 del; 60 mod
  Patch: https://git.openjdk.java.net/jdk/pull/81.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/81/head:pull/81

PR: https://git.openjdk.java.net/jdk/pull/81