[API change]
* Depend on ipynb library.
* Add `ipynb` as input and output format.
* Added Text.Pandoc.Readers.Ipynb (supports both nbformat v3 and v4).
* Added Text.Pandoc.Writers.Ipynb (supports nbformat v4).
* Added ipynb readers and writers to T.P.Readers,
T.P.Writers, and T.P.Extensions. Register the
file extension .ipynb for this format.
* Add `PandocIpynbDecodingError` constructor to Text.Pandoc.Error.Error.
* Note: there is no template for ipynb.
Previously the `.0` was interpreted as a file extension,
leading pandoc not to add `.tex` (and thus not to find the
file).
The new behavior matches tex more closely.
* These were added by the RST reader and, for literate Haskell,
by the Markdown and LaTeX readers. There is no point to
this class, and it is not applied consistently by all readers.
See #5047.
* Reverse order of `literate` and `haskell` classes on code blocks
when parsing literate Haskell. Better if `haskell` comes first.
* Ensure that we don't get > 2 levels of section nesting,
even with slide level > 2.
* If slide level == N but there is no N-level header, make
sure the next header with level > N gets treated as a slide
and put in a section, rather than remaining loose.
Closes#5168.
Underscore emphasis can't cross table cell boundaries,
but the parser wasn't respecting this, leading to exponential
behavior in documents with table cells containing underscores.
This fixes the original sample; it's possible that there
are other performance issues involving underscores.
Closes#3921.
* Add 'landmarks' id attribute to the landmarks nav.
* Replace old default CSS removing numbers from ol.toc li
with new rules that match `nav#toc ol, nav#landmarks ol`.
* We keep the `toc` class on `ol` for backwards compatibility.
* FIX#5183 : zimwiki : remove automatic colon prefix before internal images
 should be converted to {{foo.png}} (relative path)
Therefore the ':' prefix is useless and must be removed.
I never used the zimwiki, but i submitted the similar dokuwiki fix.
1. The zimwiki syntax is inspired by dokuwiki
2. The zimwiki documentation does not mention the colon character for images
3. The pandoc zimwiki writer seems to be a copy-paste for the dokuwiki writer
If the PR #5184 is applied, I think this one should be applied too.
* FIX#5183 : remove automatic ':' prefix before internal image links
`` should be converted to `{{foo.png}}` (relative path)
`
Therefore the ':' prefix is useless and must be removed.
It blocks users from making relative image links.
Update tests for DokuWiki Writer : external images
Previously we used HsYAML's decodeStrict to recognize
boolean values (treating everything else as a string).
This caused problems relating to hvr/HsYAML#7.
We now just check for the recognized boolean values
`true|True|TRUE|false|False|FALSE`, and avoid using
HsYAML.
Closes#5177.
