40C3: tours, schedule data, tour map and calendar entries

- tour-map shortcode: Leaflet map of the tour locations with routes from the
  Congress, from the map/tours sections of data/schedule/<event>.yaml; Leaflet
  and the OSMIC, Maki and Temaki icon sets vendored; 39C3 uMap data converted.
- calendar shortcode: per tour date, a pill with an .ics download (iCalendar)
  and a Google Calendar link; Font Awesome Free vendored, fa-icon partial.
- README sections for the calendar and tour map shortcodes and the map data.

assets/vendor/icons/temaki/latrine.svg

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 22 48" x="0px" y="0px">
+  <path d="M0 42.95V46.5a1.5 1.5 0 0 0 3 0V45H19v1.5a1.5 1.5 0 0 0 3 0V8H0ZM17 25a1 1 0 0 1 2 0v3a1 1 0 0 1 -2 0Z"/>
+  <path d="M16 0H6A6 6 0 0 0 0 6H22A6 6 0 0 0 16 0Z"/>
+</svg>