[docwriter] Don't break code snippets accross lines.

Reported as

  http://lists.nongnu.org/archive/html/freetype-devel/2018-08/msg00124.html

* docs/reference/markdown/stylesheets/extra.css (.md-typeset code):
Add rule `white-space'.

ChangeLog

@@ -1,3 +1,14 @@
+2018-09-03  Nikhil Ramakrishnan  <ramakrishnan.nikhil@gmail.com>
+
+	[docwriter] Don't break code snippets accross lines.
+
+	Reported as
+
+	  http://lists.nongnu.org/archive/html/freetype-devel/2018-08/msg00124.html
+
+	* docs/reference/markdown/stylesheets/extra.css (.md-typeset code):
+	Add rule `white-space'.
+
 2018-09-03  Werner Lemberg  <wl@gnu.org>
 
 	*/*: s/PSNames/psnames/.

docs/reference/markdown/stylesheets/extra.css

@@ -33,6 +33,9 @@ span.keyword {
     white-space: pre;
     color: #d73a49;
 }
+.md-typeset code {
+    white-space: pre;
+}
 /* H4 Heading */
 h4 {
     background-color: #EEEEFF;