Fix quoteless action param deprecation

This attempts to resolve the following deprecation warning which you get when using the shorthand notation for actions, etc (http://jsbin.com/jevev/2/edit)

```
DEPRECATION: Using a quoteless parameter with {{action}} is deprecated. Please update to quoted usage '{{action "blah"}}.
        at Object.handleRegisteredAction [as handler] (http://builds.emberjs.com/tags/v1.4.0/ember.js:37742:17)
        at HTMLAnchorElement.handleActionEvent (http://builds.emberjs.com/tags/v1.4.0/ember.js:21916:25)
        at Object.Ember.handleErrors (http://builds.emberjs.com/tags/v1.4.0/ember.js:907:17)
        at HTMLAnchorElement.<anonymous> (http://builds.emberjs.com/tags/v1.4.0/ember.js:21908:20)
        at HTMLBodyElement.jQuery.event.dispatch (http://code.jquery.com/jquery-2.0.2.js:4692:9)
        at HTMLBodyElement.elemData.handle (http://code.jquery.com/jquery-2.0.2.js:4377:6) 
```

I couldn't come up with a good test case for this, but that is likely because I am very new to pegjs and emblem in general. Suggestions for a test are very welcome, but it seems like this change needed to be made at a pretty low level. Here's a JSBin using an emblem.js from my branch: http://jsbin.com/jevev/1/edit - notice you can click the link without getting a warning in the console.

Also, I had to base this branch off of my other pull request to ensure the tests were all passing: https://github.com/machty/emblem.js/pull/136

Please let me know if you have any suggestions for changes, or if there is anything else I can do to help :smile: