Dev read classification

[replikation]

• [x] closes #39
• [x] read masing (30bp) before and after for kraken2
• [x] krona plot for vis
• [x] nextclade added, closes #29

[hoelzer]

@replikation great! works also on my side! please feel free to merge and release :)

I would then do another recent run with the release version as additional check