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/can.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0" y="0" viewBox="0 0 15 15">
+  <path d="M3 2.5C3.5 4 11.5 4 12 2.5C12 2.5 12 13.5 12 13.5C12 15.5 3 15.5 3 13.5C3 13.5 3 2.5 3 2.5zM9.5 1.25C10 1.25 10.5 1.5 10.5 1.75C10.5 2 10 2.25 9.5 2.25C9 2.25 8.5 2 8.5 1.75C8.5 1.5 9 1.25 9.5 1.25zM12 1.5C12 0 3 0 3 1.5C3 3.5 12 3.5 12 1.5z"/>
+</svg>