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/crane.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="M14 1.5C14.5 1.5 14.5 3 14 3C14 3 13.5 3 13.5 3L13.5 7C13.5 7.5 12.5 7.5 12.5 7L12.5 3L7.5 3L8.5 12.5C8.5 12.5 10 12.5 10 12.5C10.5 12.5 10.5 14 10 14C10 14 2 14 2 14C1.5 14 1.5 12.5 2 12.5C2 12.5 3.5 12.5 3.5 12.5L4.5 3C4.5 3 2.5 3 2.5 3C2 3 2 1.5 2.5 1.5C2.5 1.5 14 1.5 14 1.5zM7 10.25L5 10.25L4.75 12.5L7.25 12.5L7 10.25zM6.75 6.75L5.25 6.75L5.1 8.75L6.9 8.75L6.75 6.75zM6.35 3L5.6 3L5.4 5.25L6.5 5.25L6.35 3z"/>
+</svg>