Update to 2.22

Upstream changes:
2.22  2016-07-19T09:24:00
	- Revert change so we use Test::More instead of Test2::Bundle::Extended.
		See RT#115236. Thanx to ribasushi for this report, and my apologies for not acting sooner.

2.21  2016-05-22T09:21:00
	- Escape a '{' in a regexp in t/foo.t. See RT#114551. Thanx to Slaven Rezic.
	- Fix a typo in a comment, as provided by Gregor Herrmann in RT#111385.
	- See http://savage.net.au/Ron/html/My.Workflow.for.Building.Distros.html for notes on the
		modernization of the repo.
		This includes updating Makefile.PL and removing Build.PL, MANIFEST and *META.*.
	- Bail out cleanly if 'dot' is not installed. See RT#105575. Thanx Karen Etheridge.
	- Update docs to point to a copy of the Perl licence.
	- Update docs in GraphViz.pm to point to the github repo.
	- Move t/pod.t into xt/author/.

2.20  2015-12-29T08:13:00
	- Merge patch from ntyni via github. This concerned use of defined(@some_array). With thanx.

2.19  2015-11-13T08:30:00
	- No code changes.
	- Accept pull request from Patrice Clement to add the x_deprecated flag to both META.json and
		META.yml. The docs already had various references to 'deprecated', including directing users
		to GraphViz2, so no change is needed there. Thanx Patrice.
	- Add .gitignore to MANIFEST.SKIP.

2.18  2015-05-28T08:43:00
	- All patches to this version are from chrony, via a github pull request. With thanx.
	- Use File::Which on Windows to detect if Graphviz is present.
	- Clean up the code, including Build.PL and Makefile.PL.

2.17  Mon Mar 30 08:56;00 2015
	- No code changes.
	- Create github repo. This has been done because ribasushi (Peter Rabbitson) has kindly offered
		some patches. Hence I've reversed my policy of encouraging this module to die :-).
	- Update Build.PL and Makefile.PL to point to the repo. None of the pre-reqs were updated.

2.16  2014-08-30T08:25:00
	- Update docs on how to download AT&T's Graphviz.
		Thanx to Alex Becker (see RT#98405).

2.15  2013-11-28T11:23:00
	- Fix double-quote escaping bug in GraphViz's _attributes() method. See RT#90528.
		Many thanx to Smylers for the report.
	- Rename CHANGES to Changes as per CPAN::Changes::Spec.


(wen)