ebook-convert .recipe: specify number of feeds and articles

When developing recipes using the command line, allow specifying the
number of feeds and articles when using the --test parameter. Fixes #1246061 [[Enhancement] Make --test option to ebooks-convert take parameters specifying the number of feeds to download and number of items per feed to download](https://bugs.launchpad.net/calibre/+bug/1246061).
Content server: Display book title on permalink page

Fixes #1246523 [No title shown in permalink view](https://bugs.launchpad.net/calibre/+bug/1246523)
Content server: Show the most important fields (authors/series/tags) at the top in the book details view.
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