Replace Element and makeHierarchical with makeSections.

Text.Pandoc.Shared:

+ Remove `Element` type [API change]
+ Remove `makeHierarchicalize` [API change]
+ Add `makeSections` [API change]
+ Export `deLink` [API change]

Now that we have Divs, we can use them to represent the structure
of sections, and we don't need a special Element type.
`makeSections` reorganizes a block list, adding Divs with
class `section` around sections, and adding numbering
if needed.

This change also fixes some longstanding issues recognizing
section structure when the document contains Divs.
Closes #3057, see also #997.

All writers have been changed to use `makeSections`.
Note that in the process we have reverted the change
c1d058aeb1c6a331a2cc22786ffaab17f7118ccd
made in response to #5168, which I'm not completely
sure was a good idea.

Lua modules have also been adjusted accordingly.
Existing lua filters that use `hierarchicalize` will
need to be rewritten to use `make_sections`.

1 files changed, 0 insertions, 2 deletions

diff --git a/test/command/1710.md b/test/command/1710.md
index 4d9c64b30..64d86cffe 100644
--- a/test/command/1710.md
+++ b/test/command/1710.md
@@ -56,7 +56,6 @@ ok
 ^D
 \begin{frame}{Slide one}
 \protect\hypertarget{slide-one}{}
-
 \begin{columns}[T]
 \begin{column}{0.4\textwidth}
 \begin{itemize}
@@ -82,6 +81,5 @@ ok
 ok
 \end{column}
 \end{columns}
-
 \end{frame}
 ```