Also allow disabling author export.
This commit might be a big behavior change for some as now the author
name is auto-exported to the post front matter.
To disable that, simply put "#+AUTHOR:" or "#+OPTIONS: author:nil" at
the top of your Org file.
With this commit, ox-hugo now supports one more implicit ox.el
feature.
Part of solution to https://github.com/kaushalmodi/ox-hugo/issues/106
The option is set by the HUGO_CODE_FENCE property.
- If set to t (default), Markdown code fence is used.
- Else Hugo `highlight' shortcode is used.
Add examples.