Now that bootstrap-vue is no longer used we can finally deactivate the
Vue 2 compatibility mode.

This is a big one because it’s hard to make these kind of changes
atomic. This changeset reworks the calendar component which is no longer
dependent on bootstrap and vuex.

As a consequence we can remove axios, bootstrap, and vuex because the
calendar was the last remaining part of the code that was still using
them.

refs #127 #140 #261 #279

This makes it easier to set styles specifically for the wrapping
container.

refs #247

refs #276

refs #271

The image loader did not check if it reached the end of the result set
and just kept increasing the page number, spamming steering with
requests.

The dashboard should generally only check for permissions not flags.

refs #247

refs #247

refs #247

refs #239