Add HTML5 display definition

- Correct `block` display not defined for any HTML5 element in IE 8/9.
- Correct `block` display not defined for `main` in IE 11

This has repeatedly tripped people up (myself included), so it might be
time to add it to the template.
Merge pull request #97 from gemmaleigh/add-display-block-to-main

Add HTML5 display definition
Remove h2 from footer

Having a h2 in the footer can be confusing as it demands more importance
than content in the page. Replace the h2 with a paragraph, this means
that the content can still be found and read by someone looking for the
licence information.
Add rel=licence

As suggested by Brad Wright, add the appropriate relationship.

[1]: http://www.w3.org/TR/html5/links.html#link-type-license
Merge pull request #99 from alphagov/remove-footer-heading

Remove h2 from footer
Updating OGL link text and destination.

Version 3 of the OGL was released on 31st October. This updates the link text and destination and adds the rel="license" attribute.
Bump govuk_frontend_toolkit to latest version

Changes include: new helpers for creating grid layouts, support for selection-button events to be document-level, new grid helpers using %site-width-container for IE. Full details in the changelog - https://github.com/alphagov/govuk_frontend_toolkit/blob/master/CHANGELOG.md.
Merge pull request #100 from alphagov/update_ogl_licence

Update OGL licence links in footer, bumping frontend_toolkit
Bumping version to 0.10.0
expand detail of changes
Compress some of the PNG images smaller
Merge pull request #103 from alxndrsn/compress-images

Compress some of the PNG images smaller
Merge pull request #102 from alphagov/bump_version_to_0100

Bumping version to 0.10.0