Google video search thumbnails

This is a pittifully small PR. It adds rich snippet metadata to the the video mark-up, so's that the thumbnails appear in google thumbresults: See rich snippet data for before and after below: 

Note "videoobject" parsed and populate in the example below: 
http://www.google.com/webmasters/tools/richsnippets?q=uploaded:8004ffe277d306b2ea8b0b108a3d6d2f

But not here ( before changes )
http://www.google.com/webmasters/tools/richsnippets?q=http%3A%2F%2Fwww.theguardian.com%2Ffashion%2Fvideo%2F2014%2Fjul%2F30%2Fpalm-prints-summer-fashion-tips-sp-video


Please use the XHTML notation with a ` /` (space + forward slash) at the end of self closing tags.