add event time data in uniweb calendars

calendar_utils/icalevents/icalparser.py

...ns/migrations/0025_electionshomepage_calendar_and_more.py

...grations/0008_alter_greendealhomepage_content_and_more.py

shared/static/styleguide2/main.css

shared/static/styleguide2/main.js

shared/templates/shared/calendar_current_events_snippet.html

uniweb/templates/uniweb/blocks/calendar_agenda.html