Added bash script to create thumbnail for http://nrk.no

First creates a PNG of the http://nrk.no page (around 15MB).
Then shrinks the page to a 200 pixel width and finally
crops the image to the same size as the aftenposten and
vg front pages.

Requires the following debian packages:
 cutycapt (uses webkit to download a web page and render it as an image)
 xfvb (a fake X11 server that fills cutycapt's requirement for an X server)
 netpbm
Use a local thumbnail as the nrk.no cover image.
Generate nrk.no cover, and generate epub for nrk.no.
Use a JPEG for the nrk.no cover.

Reduces size from 90kB to 20kB.
Merge branch 'create-nrk-frontpage'