Add Aurora.js solution

This add [Aurora.js](https://github.com/audiocogs/aurora.js) solution to jPlayer, like are html / flash solutions.
I personally did this for the [Ampache](https://github.com/ampache/ampache) project to avoid server transcoding when it is only used because of browser compatibility issues.

To test it, get the branch and set the following jPlayer options:
```javascript
solution: 'html, flash, aurora',
auroraFormats: 'flac, m4a, mp3, oga'
```
Then include Aurora.js scripts / decoders:
```html
<script src="aurora.js"></script>
<script src="ogg.js"></script>
<script src="flac.js"></script>
<script src="opus.js"></script>
<script src="mp3.js"></script>
```

I added a new **auroraFormats** option because Aurora.js can be extended with new decoders and we cannot determine which decoder manage which format from the js api.
Aurora.js provides a limited set of events, I will attempt to pull request on Aurora.js to improve their api but better to talk here before ; if this has some interest.