changelog for gatherdir
require that the extension is dotless
make MVP RootSection respect ":version" for Dist::Zila
v4.300029

          allow :version directive in root section to require a given version
          of Dist::Zilla

          simply and speedify some of GatherDir (Thanks, Olivier Mengué!)
Improve the Plugin::Pod* documentation.

Add synopses, and references to "dzil test --release".