Some fixes

I just fixed some typos I found while reading.
I also noticed that `<`s are removed if there's a char in front of them although the HTML entities (`&lt;`) are in the [code](https://github.com/aurajs/aura/blob/gh-pages/index.html#L194):
```html
<div class='row'>
  <div class='span4' data-aura-widget="issues" data-aura-repo="aurajs/aura">div>
  <div class='span4' data-aura-widget="issues" data-aura-repo="emberjs/ember.js">div>
  <div class='span4' data-aura-widget="issues" data-aura-repo="documentcloud/backbone">div>
div>

<div data-aura-widget="hello">div>
```
```javascript
define({
  initialize: function () {
    this.$el.html('<h1>Hello Aurah1>');
  }
});
```

Could this behavior be produced by some bad code highlighter?