Add social bar to YC

Add social bar to storefront with:
1. facebook like

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<iframe src="//www.facebook.com/plugins/like.php?href=http%3A%2F%2Fdevelopers.facebook.com%2Fdocs%2Freference%2Fplugins%2Flike&send=false&layout=button_count&width=100&show_faces=false&font=arial&colorscheme=light&action=like&height=21" scrolling="no" frameborder="0" style="border:none; overflow:hidden; width:100px; height:21px;" allowTransparency="true"></iframe>
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2. g+

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<!-- Place this tag where you want the +1 button to render. -->
<div class="g-plusone" data-size="medium"></div>

<!-- Place this tag after the last +1 button tag. -->
<script type="text/javascript">
(function()

{ var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); }

)();
</script>
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3. twitter

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<a href="https://twitter.com/share" class="twitter-share-button" data-hashtags="yes-cart">Tweet</a>
<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>
====