tighten up entries
if there are no keywords, add nothing to metadata
TODO tests for proper metadata merging when two plugins are employed at once
only one keyword string is ever extracted
encoding fixes (will need to be updated when PPI and Dist::Zilla::Role::PPI are encoding-aware)
decode_json() already decodes as utf8
test the debug log line too
remove unneeded plugin
Dist-Zilla-Plugin-Keywords-0.005

          - no longer adding an empty arrayref to metadata if there is no
            data to add
          - properly handle utf8 (or other)-encoded keyword strings