rotating unit cards transition

[DreadKnight]

In dash view, after a little bit of time since a new unit was selected, the cards should spin around and show the cards of the newly selected unit. The small delay is used to avoid making this very distracting / annoying, especially when the mouse wheel is being used to browse between units at a fast speed.

We should probably adopt Vue.js first in order to easily pick up an already coded solution for this https://vuejsexamples.com/generic-flip-card-in-vue-that-allows-completely-arbitrary-content-on-each-side/