- For LineEnding use lowercase constructors, e.g. `crlf`, `native`.
This was the original intent, but there was a bug in the
implementation.
- For HTMLSlideVariant use lowercase constructors.
- For ReaderOptions use e.g. `default-image-extension`
instead of `readerDefaultImageExtension` for field names.
- For Extension, use e.g. `tex_math_dollars` instead of
`Ext_tex_math_dollars` as constructor.
- For Extensions, use an array of Extensions, instead of
an object wrapping the tag `Extensions` and an integer.
(The representation is not supposed to be part of the
public API.)
- For Opt, use field names like `tab-stop` instead of `optTabStop`.
Fix broken links in doc/epub.md, doc/getting-started.md,
doc/customizing-pandoc.md, doc/using-the-pandoc-api.md.
Also, use absolute links to pandoc.org when possible, so that
the links can be followed by people viewing these documents
on GitHub.
