Search items from text

Search from text instead of html.

I want to use chosen with [Ember.js](http://emberjs.com).
Its template language inserts `<script>` into chosen item.

Such as:

``` html
<ul class="chzn-results">
  <li id="ember592_chzn_o_1" class="ember-view active-result" style="">
    <script id="metamorph-5-start" type="text/x-placeholder"></script>
    item 1
    <script id="metamorph-5-end" type="text/x-placeholder"></script>
  </li>
  <li id="ember592_chzn_o_2" class="ember-view active-result" style="">
    <script id="metamorph-6-start" type="text/x-placeholder"></script>
    item 2
    <script id="metamorph-6-end" type="text/x-placeholder"></script>
  </li>
</ul>
```

In this case, search form is broken by using html for search items.
![ 2013-04-02 15 30 37](https://f.cloud.github.com/assets/290782/327058/d6b32d04-9b60-11e2-81ee-1edae0ec5a60.png)

So I use text for search item.