add function js to get share count

includes javascript breakpoint query commented out
if the getShareCounts function is available, call it
add .js-sharecount placeholder to social_share html
style the share count to draw more attention
add onmediaquery.js and required scss

to detect current breakpoint in js
use onmediaquery to stop animation on small screens
require MQ function to run getShareCounts
only add to share count if there are more than 4 shares
get the current url rather than hard code production url
Don't add extra slash in URL
Tidy up extra space and indentation only
Merge pull request #1008 from openaustralia/share_count

display the share count