WIP: Add per device view and jazz all up with CSS
With this MR
- the landing page now uses a CSS grid view instead of a table
- a per-device view is added
- in the per-device view the traces results are shown as overlay when JS is enabled (using external fancybox for now, could be put into static), otherwise they are just handled as normal links. This could also be done for the landing page
- The templates are reworked to make it possible to switch the header for the overlay
- results view has now summary pass/fail icon (one could also switch the header background color - fancy)
Known bugs: Sometimes the traces are listed more than once on the result page, this is probably a race condition when loading the results: If two processes create a Future for the same job, then they will probably also be stored in the DB as different objects. I'n not sure whether this was there before or whether this is triggered by the use of fancybox