Site build with Workgroups page

+ latest build with Workgroups sample page
+ add RDF Data Shapes W3C group
+ Add a border to the drop down box
+ Fix flex/flag body widths in Firefox
+ Simplify markup of .activeFilter button for bartender; fixes text
overflow in Firefox
+ Add "[sample]" to the Workgroups sample page title
+ Add space for "listing_description" which a lot of listings need

Close #19