Are the showdown extension supposed to work? Or not yet?

[Ilyes512]

First of, very nice project :) I like the "ghost" way of writing.

So I am testing your plugin and I got it installed and running. Tested some basic stuff like emphasis and bold text and that all worked.

In the settings>writing I noticed "showdown extension's". Are these supposed to work, cause I selected github.js and tried it out by typing this without succes:

```php
<?php
echo 'Testing';
\```

Do I need to load the github.js myself or adjust my theme in anyway for it to work?