RFR: JDK-8263043: Add test to verify order of tag output [v2]

[Jonathan Gibbons]

> Please review a new test to verify that the output of block tags is generated in the expected order.
> 
> The code in the standard doclet to generate the output is the same for all use sites (modules, packages, class, members) and so just the richest site is tested.
> 
> The test checks that tags appear in the expected order by default, but can be reordered in a couple of different ways.

Jonathan Gibbons 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 four additional commits since the last revision:

 - Address review comments; extend test to check @author and @version in class comments
 - Merge remote-tracking branch 'upstream/master' into tag-order
 - fix whitespace
 - JDK-8263043: Add test to verify order of tag output

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2835/files
  - new: https://git.openjdk.java.net/jdk/pull/2835/files/3d3bdf90..395cca1b

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2835&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2835&range=00-01

  Stats: 1388 lines in 45 files changed: 1108 ins; 95 del; 185 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2835.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2835/head:pull/2835

PR: https://git.openjdk.java.net/jdk/pull/2835