templates: collection-aware search frame

* Collection-specific pages are now different from the Home page.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
fixtures: initial set up for collections

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
templates: collection pages link to submit pages

* Collection splash pages now link to corresponding deposition pages.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
deposit: autofill update & LHCb form update

* Authors now autofill (though they don't show until refreshed)

* LHCb form updated #13

* Minor form layout updates