Implement Camp23 event list

src/plainui/jinja2.py

src/plainui/jinja2/plainui/components/list_events.html

src/plainui/jinja2/plainui/fahrplan.html

src/plainui/locale/de/LC_MESSAGES/django.po

src/plainui/locale/en/LC_MESSAGES/django.po

...lainui/static/plainui/fonts/SairaStencilOne-Regular.woff2

src/plainui/styles/_import-fonts.scss

src/plainui/styles/components/_buttons.scss

src/plainui/styles/components/_event.scss

src/plainui/styles/hub-assembly.scss