Support fenced code block in list.

It would be great if we can do something like this:

• A list item with some code sample

  console.log('hello, world.');
  

[minwe]

How about this?

Code blocks nested in blockquote are not rendered correctly. It should be a <pre><code>...</code></pre>, but in Ghost got just <code>。

Take below as example:

> Note:
>
> Some code in blockquote.
>
> ```javascript
> function() {
>   consoel.log('hello world!');
> }
> ```

This block is rendered to:

<blockquote>
  <p>Note:</p>

  <p>Some code in blockquote.</p>

  <p><code>javascript
  function() {
    consoel.log('hello world!');
  }
  </code></p>
</blockquote>

The correct result should be:

<blockquote>
  <p>Note:</p>

  <p>Some code in blockquote.</p>

<pre><code class="javascript language-javascript">function() {
  consoel.log('hello world!');
}</code></pre>
</blockquote>

The official demo of Showdown works well.

Marked works well, too.

So why do not use the official version of Showdown, the Ghost fork is out of date and bugly.

[draveness]

When will fenced code block be supported in Ghost? Have been waiting for this for a long long time