v2.3.5

A major refactor of how shelf and cover sizes are calculated, so the layout behaves consistently across different screens and resolutions.

• Most people will notice no difference.
• The small / medium / large size settings now respond more predictably; if your shelf looks different you may want to readjust them to taste.
• Square and landscape covers (such as "The Complete Peanuts") now fill their slot by cropping to the centre instead of being stretched out of shape.
• Fixed a rare crash some users could hit when opening the bookshelf at certain screen sizes.