Update GOV.UK template
Update proposition header to Spotlight-ish

I haven't included all the links that we have in Spotlight here. This
is because those links are going to change over time and they're never
going to be kept consistent, so I don't even want to try.
Add Q2 2014 data (April 2013 to March 2014)
Merge pull request #151 from alphagov/update-data-apr-2013-mar-2014

Data update: April 2013 to March 2014