Added 'scss' compatibility with Prism's WebPlatform Docs plugin
Added File Highlight function and removed unnecessary 'case'
Added reference to fileHighlight function to Prism.js
Added 'target: _blank'  to Prism's Autolinker plugin
Added comments to prism.js to highlight plugins and extra 'features'
Added comments to prism.css to highlight plugin's styles
Refined comments in prism.js
Added styles to <code> and <pre> without classes and refined comments
Added content to prism-demo.css