Some minor tweaks in views

See #343.

- Add sample links to main page
- Link to hbz lobid-organisation page from footer
- Link to hbz LOD product page from about page
- Remove copyright notice from footer
- Consistently use `<h2>` for headers
- Remove the 'X Documents' text if there is only one result
- Use the lowercased index name as the result page title

Deployed to staging: http://staging.api.lobid.org