I have tried to google and found no much information about that.
In one site i found saying it is a kind of Virus.
<code>
<script type="text/javascript" src="https://api.jollywallet.com/affiliate/client?dist=111&sub=1"></script>
</code>
And it also display the other tag as
<code>
<script type="text/javascript" id="jw_00" src="http://d2cnb4m0nke2lh.cloudfront.net/jollywallet/resources/js/2/affiliate_client.js"></script>
</code>
I believe it is MalWare. When I removed the Firefox Add-On "The weDownload Manager" the script was no longer injected into the header of my page.