- new UI language: Slovak, kindly contributed by [Milan](https://hosted.weblate.org/user/Milan/)
  who also corrected/updated the Czech translation.
- #131 Added https://www.databazeknih.cz for looking up Czech+Slovak books
- #125 allow grouping by "original language"
- #86 Identifiers for Authors and providing a "View on…" menu.

FIXES:

- #113/#129 rewritten the group-level summation of the books in that group
  making it several orders of magnitude faster.
- #120 improvements to scrolling to the correct book
