More bold

- make the filter rss feed icon sit inline with the filter summary
- make 'biography' heading on minister pages bold
- make the 'world location' counter big and bold
Remove subsection from static history titles

It was decided that this was visuall noise which didn't add much. It
also made the structure look more complicated than it was and made
things confusing.

https://www.pivotaltracker.com/story/show/48113761
Merge pull request #451 from alphagov/typography-nitpicking

More bold