Bump govuk_template and update footer

Update govuk_template for new fixed width IE and standardised padding
on the footer to match the header.

The footer was wider than the header on anything below 1024 width. This
changes the markup so it now matches the header grid and resizes at the
same points as the header and the copyright notice below it.

Moved to two floated elements of 1/3rd and 2/3rd widths respectivly
rather than elements close to those widths.

Updated code to use the `media` mixin rather than the `media-down` which
meant we were able to reduce a large amount of code.

Added a `<hr>` for the break between the links and the copyright as
couldn't use a border on any elements as they were `15px` to wide on
either side due to them containing floated elements which managed their
own gutter.

I have taken screenshots of how the footer now looks in various browsers: 

https://drive.google.com/a/digital.cabinet-office.gov.uk/folderview?id=0BxQACykuSGl7WDJWZkJ0QmgwVGM&usp=sharing