fix pod links
properly detect and prevent two copies of the plugin from running
debug logging statements
accomodate future versions of MB/MBT also implementing gather_files

This is covered by the changes in:

https://github.com/rjbs/Dist-Zilla/pull/229
https://github.com/Leont/dist-zilla-plugin-modulebuildtiny/pull/4
add mailing list and irc info to metadata
Dist-Zilla-Plugin-ModuleBuildTiny-Fallback-0.002

          - minor doc fixes
          - handle some potential future changes to [ModuleBuild],
            [ModuleBuildTiny]