decorating markup

this is in response to issue #3
@adamclerk There is a slight security risk here by using `.html`. Can you update this to append the message using `.text` method?

```coffeescript
message = $('<span class="msg"/>').text(message);
appendFunction = => ircOutput.append line.html(util.format '<span class="ts">%s<span> <span class="un">%s</span> %s', new Date().toLocaleTimeString(), from, message.html())
```

I know that atom will block script eval, however this means links posted become active and images become viewable if the message comes in as the proper html.

I'm not so sure this is desirable, and there could be other execution risks that I'm not thinking about.