Search Page UI improvements

[zephod]

[Refactored] :: Follows on from #1506 UX changes.

• Declutter the sidebar. No yellow box.
• Facets to go on the left, rather than the right. More logical flow.
• Did you know you can search by author? Probably not. Find a nice way of presenting extended search options.
• Make Datasets in the search page look more like Datasets on the groups pages (ie. like awesome sexy search results).
  • Update that look-and-feel to include the new resource icons created in #1506

[rgrp]

Quite a bit of this is now duplicated in other tickets e.g. #1506. Decide what isn't and it's priority (do not have to implement).