Support verses

Line breaks, indentation and blank lines stay preserved in Org verse
blocks.

example-site/content-org/all-posts.org

@@ -812,6 +812,57 @@ Quote 3. This is a multi-paragraph quote.
 This is the second paragraph.
 #+END_QUOTE
 Some other text.
+* Verse                                                               :verse:
+** One verse
+:PROPERTIES:
+:EXPORT_DATE: 2017-08-01
+:EXPORT_FILE_NAME: one-verse
+:END:
+To preserve the line breaks, indentation and blank lines in a region,
+but otherwise use normal formatting, you can use the /verse/
+construct, which can also be used to format poetry -- [[http://orgmode.org/manual/Paragraphs.html][Reference]].
+#+BEGIN_VERSE
+Great clouds overhead
+Tiny black birds rise and fall
+Snow covers Emacs
+
+    -- AlexSchroeder
+#+END_VERSE
+** Consecutive verses
+:PROPERTIES:
+:EXPORT_DATE: 2017-08-01
+:EXPORT_FILE_NAME: consecutive-verses
+:END:
+#+BEGIN_VERSE
+Tyger Tyger, burning bright,
+In the forests of the night;
+What immortal hand or eye,
+Could frame thy fearful symmetry?
+
+In what distant deeps or skies.
+Burnt the fire of thine eyes?
+On what wings dare he aspire?
+What the hand, dare seize the fire?
+
+   -- "The Tyger" /by/ William Blake
+#+END_VERSE
+#+BEGIN_VERSE
+Some parts can be *bold*
+  Some can be =monospace=
+    Some can be /italic/ too.
+#+END_VERSE
+#+BEGIN_VERSE
+What is this life if, full of care,
+We have no time to stand and stare.
+
+No time to stand beneath the boughs
+And stare as long as sheep or cows.
+
+No time to see, when woods we pass,
+Where squirrels hide their nuts in grass.
+
+   -- "Leisure" /by/ William Henry Davis
+#+END_VERSE
 * TODO Pre-Draft State
 :PROPERTIES:
 :EXPORT_FILE_NAME: draft-state-todo

example-site/content/posts/consecutive-verses.md

@@ -0,0 +1,33 @@
++++
+title = "Consecutive verses"
+date = 2017-08-01
+tags = ["verse"]
+draft = false
++++
+
+Tyger Tyger, burning bright,<br />
+In the forests of the night;<br />
+What immortal hand or eye,<br />
+Could frame thy fearful symmetry?<br />
+<br />
+In what distant deeps or skies.<br />
+Burnt the fire of thine eyes?<br />
+On what wings dare he aspire?<br />
+What the hand, dare seize the fire?<br />
+<br />
+&#xa0;&#xa0;&#xa0;-- "The Tyger" _by_ William Blake<br />
+
+Some parts can be **bold**<br />
+&#xa0;&#xa0;Some can be `monospace`<br />
+&#xa0;&#xa0;&#xa0;&#xa0;Some can be _italic_ too.<br />
+
+What is this life if, full of care,<br />
+We have no time to stand and stare.<br />
+<br />
+No time to stand beneath the boughs<br />
+And stare as long as sheep or cows.<br />
+<br />
+No time to see, when woods we pass,<br />
+Where squirrels hide their nuts in grass.<br />
+<br />
+&#xa0;&#xa0;&#xa0;-- "Leisure" _by_ William Henry Davis<br />

example-site/content/posts/one-verse.md

@@ -0,0 +1,16 @@
++++
+title = "One verse"
+date = 2017-08-01
+tags = ["verse"]
+draft = false
++++
+
+To preserve the line breaks, indentation and blank lines in a region,
+but otherwise use normal formatting, you can use the _verse_
+construct, which can also be used to format poetry -- [Reference](http://orgmode.org/manual/Paragraphs.html).
+
+Great clouds overhead<br />
+Tiny black birds rise and fall<br />
+Snow covers Emacs<br />
+<br />
+&#xa0;&#xa0;&#xa0;&#xa0;-- AlexSchroeder<br />

ox-blackfriday.el

@@ -78,8 +78,8 @@
                      (example-block . org-blackfriday-example-block)
                      (table-cell . org-blackfriday-table-cell)
                      (table-row . org-blackfriday-table-row)
-                     (table . org-blackfriday-table)))
-
+                     (table . org-blackfriday-table)
+                     (verse-block . org-blackfriday-verse-block)))
 
 
 ;;; Transcode Functions
@@ -339,6 +339,23 @@ contextual information."
     ;; (message "[ox-bf-table DBG] Tbl:\n%s" tbl)
     tbl))
 
+;;;; Verse Block
+(defun org-blackfriday-verse-block (_verse-block contents info)
+  "Transcode a VERSE-BLOCK element from Org to partial HTML.
+CONTENTS is verse block contents.  INFO is a plist holding
+contextual information."
+  ;; Replace leading white spaces with non-breaking spaces.
+  (replace-regexp-in-string
+   "^[ \t]+"
+   (lambda (m)
+     (org-html--make-string (length m) " "))
+   ;; Replace each newline character with line break.  Also
+   ;; remove any trailing "br" close-tag so as to avoid
+   ;; duplicates.
+   (let* ((br (org-html-close-tag "br" nil info))
+	  (re (format "\\(?:%s\\)?[ \t]*\n" (regexp-quote br))))
+     (replace-regexp-in-string re (concat br "\n") contents))))
+
 ;;;; Table of contents
 (defun org-blackfriday-format-toc (headline info)
   "Return an appropriate table of contents entry for HEADLINE.