Revert of Check in a simple pure-python based Markdown previewer.

third_party/Python-Markdown/markdown/extensions/nl2br.py

-"""
-NL2BR Extension
-===============
-
-A Python-Markdown extension to treat newlines as hard breaks; like
-GitHub-flavored Markdown does.
-
-See <https://pythonhosted.org/Markdown/extensions/nl2br.html>
-for documentation.
-
-Oringinal code Copyright 2011 [Brian Neal](http://deathofagremmie.com/)
-
-All changes Copyright 2011-2014 The Python Markdown Project
-
-License: [BSD](http://www.opensource.org/licenses/bsd-license.php)
-
-"""
-
-from __future__ import absolute_import
-from __future__ import unicode_literals
-from . import Extension
-from ..inlinepatterns import SubstituteTagPattern
-
-BR_RE = r'\n'
-
-
-class Nl2BrExtension(Extension):
-
-    def extendMarkdown(self, md, md_globals):
-        br_tag = SubstituteTagPattern(BR_RE, 'br')
-        md.inlinePatterns.add('nl', br_tag, '_end')
-
-
-def makeExtension(*args, **kwargs):
-    return Nl2BrExtension(*args, **kwargs)