Markdown2

- [pull 156] Footnotes XML compatibility.
- [pull 157] Horizontal rule minimum length.
- [pull 162] Fix escaping fenced code block with safe mode
- [pull 163] Fix code highlight with safe mode

- [issue 142 pull 141] Fix parentheses and spaces in urls.
- [issue 88 issue 95 pull 145] Fix code blocks in code blocks with syntax highlighting.
- [issue 113 issue 127 via pull 144] Fix fenced-code-blocks html and code output.
- [pull 133] Unify the -/= and style headers and fix TOC order
- [pull 146] tag-friendly extra to require that atx headers have a space after

- [issue 135] Fix fenced code blocks odd rendering.
- [pull 138] specify shell in Makefile
- [pull 130] break-on-newline extra
- [pull 140] Allow html-classes for img
- [pull 122] Allow parentheses in urls

- ["nofollow" extra, issue 74, pull 104] Add `rel="nofollow"` support
(mostly by https://github.com/cdman):

$ echo '[link](http://example)' | markdown2 -x nofollow
<p><a rel="nofollow" href="http://example">link</a></p>

Limitation: This *can* add a duplicate 'rel' attribute to raw HTML links
in the input.

- ["toc" extra] Unescape Markdown special chars in TOC entries. See
<https://github.com/trentm/restdown/issues/15>.

- Now 'tox' testing support (by github.com/msabramo):

[sudo] pip install tox
tox

confirming that markdown2 works with jython (not sure which version) and
pypy! Also added pypy to travis-ci testing
(http://travis-ci.org/#!/trentm/python-markdown2).

- [issue 90] Add a `Markdown.preprocess(text) -> text` hook for subclasses.
This is a match for the `Markdown.postprocess(text) -> text` hook added in
an earlier version. (by joestump).

- [issue 90, backward incompatible change] Require a space between the ''
and a text for a title. I.e.:

This still works

This doesn't work

Nor this

This keeps comments, hash tags, and ticket numbers at the beginning of the
line from turning into an h1. (by joestump)

This is a backward incompatible change, however small, hence the version
change to 2.0.0.