removed directive to set viewport width to device width

doing this allows me to be able to an icon to home screen on iphone5 which will load in full screen mode

my html file looks like

```html
<!DOCTYPE HTML>

<html>
<head>
    <title>mygame</title>

    <meta name="viewport" content="user-scalable=0, initial-scale=1.0">
    <meta name="apple-mobile-web-app-capable" content="yes" />
    <link rel="apple-touch-icon" href="/assets/icon.png" />
    <script type="text/javascript" src="mygame.js"></script>
</head>

<body onload="mygame.start()">

</body>

</html>
```

I havent tested but im assuming my addition of the ```viewport``` meta tag is redundant