Convert to Dist::Zilla

[kenahoo]

I'd like to use Dist::Zilla to manage the dist.

There are still several things to fix before we pull this in, mostly custom stuff we do during packaging:

• the <remove_me> stuff in Build.PL
• make sure the generated MANIFEST is really the same
• generate a META.json
• verify that META.yml contains what it's supposed to contain
• =item <autogenerated_accessors> in lib/Module/Build/API.pod
• the <action_list> in lib/Module/Build.pm POD
• can't let zilla set $VERSION in lib/Module/Build/Base.pm automatically, omitting it causes a compile error when we use $VERSION later in the code.

[kenahoo]

We also have to keep the manual $VERSION assignment in lib/Module/Build.pm, because (at least) the realclean action depends on having a version defined. The real problem here is probably that we're running code directly from lib/.

[Leont]

Not entirely sure it's a good idea to do this. Dogfooding can help against breaking stuff.

Either way, I released a Substitute plugin for dzil, that should make the rewriting of <autogenerated_accessors> and <action_list> easier.