Optimize search result page

[mjansing]

iQvoc's search page and search result listing should be optimized to improve usability.

Some points:

• [ ] there is just a little space to show search results (especially on small screens because of the huge input form)
• [ ] it's not clear if a search result is a concept or a collection

[youngbrioche]

• [ ] Replace URI in federated search results with instance name