Dependency and Metadata fixes.

[kentfredric]

When I wrote #17, I wrote the tests with the assumption HTTP::Tiny::Mech and WWW::Mechanize::Cached would be optional.

However, Autoprereqs has determined them to be mandatory, and this creates a few needless headaches installing dependencies. ( I personally get stuck somewhere because Cache::Cache fails )

So this patch rectifies this using Dist::Zilla::Plugin::Prereqs::Soften which moves the deps from test.requires to test.recommends.

However, at present, test.recommends vanish into a black hole, because dist.ini only uses META.yml, which only supports the Meta 1.5 spec, and thus, only supports the old crufty options, and none of the new fancy stuff like 'recommends'. ( Amongst other things ).

While I was there, I noticed a great number of contributors presently go unrecognised ( git shortlog ), and so I added [Git::Contributors] to vivify x_contributors so that MetaCPAN can show them.

[kentfredric]

The general repository tweaks have been nuked from this pull request to help accelerate the process with less subjectivism. Now this pull request only fixes problems.

[mickeyn]

@kentfredric 👍