Revision history for Facebook-InstantArticle
0.14    2017-11-28
        - Merged pull request #1 (manwar), adding [MetaJSON] to dist.ini, for
          generating META.json.
        - Added 'is_valid' method. At the moment this only do very simple checks
          to see if the Instant Article is valid or not.
0.13    2017-10-13
        - The "fb:use_automatic_ad_placement" property's content is now set to
          "enable=true ad_density=default" instead of just "true".
0.12    2016-12-09
        - Removed 'description' field in the InstantArticle object, as Facebook
          wants the article description/ingress/preamble as 'subtitle' (which is
          tagged with 'h2').
0.11    2016-09-21
        - Fixed an error in the documentation.
0.10    2016-09-20
        - Relaxed version dependencies.
0.09    2016-09-19
        - Better validation when adding elements to the article; Mojo::Log is
          used for spitting out warnings when appropriate.
        - Improved tests.
        - Improved documentation.
0.08    2016-09-17
        - Ignore empty paragraphs.
        - Corrected validation logic, but still no overall validation.
        - Improved tests.
0.07    2016-09-16
        - Allow automatic ad placement meta setting.
0.06    2016-09-12
        - Added 'add_analytics'.
0.05    2016-08-30
        - Added 'add_map'.
        - Improved 'add_embed'.
0.04    2016-08-23
        - Added 'add_heading'.
0.03    2016-08-22
        - Minor fixes.
0.02    2016-08-22
        - Added 'add_embed'.
0.01    2016-08-22
        - Initial release.