Markdown recipe

Some notes for using markdown.

In console:
```
npm install --save helper-markdown     
```

In code:
```
OriginalHandlebars.registerHelper('markdown', require('helper-markdown')());
```

Template:
```
{{#markdown}}
  {{text}}
{{/markdown}}
```

Use:
```
Handlebars.templates.Simple_html({ text: '# hello'});
```