Introduce overview with used keywords for better grouping possibilities and statistics #30
Description
On the one hand, this could just be another tab called "Keywords", and the data collected could look like this:
- Schicksalstragödie (7)
- Mord (13)
- Blabla (27)
- …
On the other hand, it would be great to have a linkable URL per keyword, something like https://einakter.dracor.org#keyword=schicksalstragodie, which would show all plays matching a certain keyword.