Add Styling of Facebook and LinkedIn buttons (horizontal style), Update Facebook Share API call, Update FB share count format

Added
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Added a .css and .min.css file (can supply .less if you want) for the horizontal style facebook and linkedin share buttons.
Added facebook share_count formatting to be more in keeping with real numbers (12.5k instead of 12500)

Updated
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Updated the facebook and linkedin transclude templates to allow for styling
Updated facebook share API to use 'share' method instead of 'feed'
Updated the README.md file to link to an updated plunkr as well as minor tweaks to the copy and directives