select: Add ability to navigate by typing #531

to avoid copy-paste:
```js
var i = index - 1, len = items.length;
while(i < len) {
    if(i === items.length - 1) {
        i = 0;
        len = index;
    }
    if(this._keyboardSearchCheckItem(items[i], lc.text)) {
        lc.index = i;
        return items[i];
    }
    i++;
}
```
doesn't test it — but idea should be clean