set of updates for Polish recipes
Pre-create error formats
Highlight cursor line
Keep only useful entries in the color theme
Line numbers
Bulk metadata edit: Fix clearing of series and publishers

Bulk metadata edit: Only clear series if the clear series checkbox is
checked. Also add a clear checkbox for publishers, so that publishers
can be removed. Fixes #1245058 [Calibre is deleting Series field even when it's not being modified](https://bugs.launchpad.net/calibre/+bug/1245058)
Method to launch editor widget in its own dialog
Syntax highlight namespace prefixes
Amazon metadata download: Fix spurious ratings for unrated books

Amazon metadata download: Fix spurious ratings being returned for
unrated books. Fixes #1245449 [Amazon source picks up ratings from ANY book on the page (suggested etc)](https://bugs.launchpad.net/calibre/+bug/1245449)
Parse CDATA tags and fix errors in bad attribute parsing
Highlight text enclosed by  heading/bold/italic tags
Syntax highlight non-breaking spaces
Refactor boilerplate functionality into base class
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More refactoring
Driver for Nook Glowlight
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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