AsciiDoc writer: use single-line section headers.

The underline style is now deprecated.
Previously `--atx-headers` would enable the single-line
style; now the single-line style is always used.

Closes #5038.

1 files changed, 32 insertions, 63 deletions

diff --git a/test/writer.asciidoc b/test/writer.asciidoc
index 4dca188e4..8bae169f1 100644
--- a/test/writer.asciidoc
+++ b/test/writer.asciidoc
@@ -1,5 +1,4 @@
-Pandoc Test Suite
-=================
+= Pandoc Test Suite
 John MacFarlane; Anonymous
 July 17, 2006
 
@@ -8,40 +7,31 @@ markdown test suite.
 
 '''''
 
-Headers
--------
+== Headers
 
-Level 2 with an link:/url[embedded link]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+=== Level 2 with an link:/url[embedded link]
 
-Level 3 with _emphasis_
-^^^^^^^^^^^^^^^^^^^^^^^
+==== Level 3 with _emphasis_
 
-Level 4
-+++++++
+===== Level 4
 
-Level 5
+====== Level 5
 
-Level 1
--------
+== Level 1
 
-Level 2 with _emphasis_
-~~~~~~~~~~~~~~~~~~~~~~~
+=== Level 2 with _emphasis_
 
-Level 3
-^^^^^^^
+==== Level 3
 
 with no blank line
 
-Level 2
-~~~~~~~
+=== Level 2
 
 with no blank line
 
 '''''
 
-Paragraphs
-----------
+== Paragraphs
 
 Here’s a regular paragraph.
 
@@ -56,8 +46,7 @@ here.
 
 '''''
 
-Block Quotes
-------------
+== Block Quotes
 
 E-mail style:
 
@@ -99,8 +88,7 @@ And a following paragraph.
 
 '''''
 
-Code Blocks
------------
+== Code Blocks
 
 Code:
 
@@ -124,11 +112,9 @@ These should not be escaped:  \$ \\ \> \[ \{
 
 '''''
 
-Lists
------
+== Lists
 
-Unordered
-~~~~~~~~~
+=== Unordered
 
 Asterisks tight:
 
@@ -166,8 +152,7 @@ Minuses loose:
 * Minus 2
 * Minus 3
 
-Ordered
-~~~~~~~
+=== Ordered
 
 Tight:
 
@@ -201,8 +186,7 @@ Item 1. graf two. The quick brown fox jumped over the lazy dog’s back.
 2.  Item 2.
 3.  Item 3.
 
-Nested
-~~~~~~
+=== Nested
 
 * Tab
 ** Tab
@@ -226,16 +210,14 @@ Same thing but with paragraphs:
 * Foe
 3.  Third
 
-Tabs and spaces
-~~~~~~~~~~~~~~~
+=== Tabs and spaces
 
 * this is a list item indented with tabs
 * this is a list item indented with spaces
 ** this is an example list item indented with tabs
 ** this is an example list item indented with spaces
 
-Fancy list markers
-~~~~~~~~~~~~~~~~~~
+=== Fancy list markers
 
 1.  begins with 2
 2.  and now 3
@@ -267,8 +249,7 @@ B. Williams
 
 '''''
 
-Definition Lists
-----------------
+== Definition Lists
 
 Tight using spaces:
 
@@ -348,8 +329,7 @@ orange::
   1.  sublist
   2.  sublist
 
-HTML Blocks
------------
+== HTML Blocks
 
 Simple block on one line:
 
@@ -411,8 +391,7 @@ Hr’s:
 
 '''''
 
-Inline Markup
--------------
+== Inline Markup
 
 This is _emphasized_, and so _is this_.
 
@@ -441,8 +420,7 @@ spaces: a^b c^d, a~b c~d.
 
 '''''
 
-Smart quotes, ellipses, dashes
-------------------------------
+== Smart quotes, ellipses, dashes
 
 ``Hello,'' said the spider. ```Shelob' is my name.''
 
@@ -463,8 +441,7 @@ Ellipses…and…and….
 
 '''''
 
-LaTeX
------
+== LaTeX
 
 * 
 * latexmath:[$2+2=4$]
@@ -489,8 +466,7 @@ Here’s a LaTeX table:
 
 '''''
 
-Special Characters
-------------------
+== Special Characters
 
 Here is some unicode:
 
@@ -544,11 +520,9 @@ Minus: -
 
 '''''
 
-Links
------
+== Links
 
-Explicit
-~~~~~~~~
+=== Explicit
 
 Just a link:/url/[URL].
 
@@ -568,8 +542,7 @@ mailto:nobody@nowhere.net[Email link]
 
 link:[Empty].
 
-Reference
-~~~~~~~~~
+=== Reference
 
 Foo link:/url/[bar].
 
@@ -593,8 +566,7 @@ Foo link:/url/[bar].
 
 Foo link:/url/[biz].
 
-With ampersands
-~~~~~~~~~~~~~~~
+=== With ampersands
 
 Here’s a http://example.com/?foo=1&bar=2[link with an ampersand in the URL].
 
@@ -604,8 +576,7 @@ Here’s an link:/script?foo=1&bar=2[inline link].
 
 Here’s an link:/script?foo=1&bar=2[inline link in pointy braces].
 
-Autolinks
-~~~~~~~~~
+=== Autolinks
 
 With an ampersand: http://example.com/?foo=1&bar=2
 
@@ -627,8 +598,7 @@ or here: <http://example.com/>
 
 '''''
 
-Images
-------
+== Images
 
 From ``Voyage dans la Lune'' by Georges Melies (1902):
 
@@ -638,8 +608,7 @@ Here is a movie image:movie.jpg[movie] icon.
 
 '''''
 
-Footnotes
----------
+== Footnotes
 
 Here is a footnote reference,footnote:[Here is the footnote. It can go
 anywhere after the footnote reference. It need not be placed at the end of the