Make tail charts interactive

[genedan]

The tail charts are static bitmaps, which makes it difficult to visually inspect fine-grained changes in the selection.

It seems like there may be ways to make the charts interactive, such as getting tooltips when hovering over points, highlighting selected series, etc.

https://matplotlib.org/3.1.1/users/navigation_toolbar.html

https://stackoverflow.com/questions/7908636/how-to-add-hovering-annotations-to-a-plot

https://stackoverflow.com/questions/43114508/can-a-pyqt-embedded-matplotlib-graph-be-interactive