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/military_checkpoint.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg viewBox="0 0 15 15" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+  <path d="M14 7L14 13.5C14 13.5 14 13.5 14 13.5C14 13.78 13.77 14 13.5 14L8 13.98L14 7ZM7 13.5L7 9L2 9C1.45 9 1 8.55 1 8C1 7.45 1.45 7 2 7L12.5 7L7 13.5ZM12.46 5.42C11.98 6.1 11.26 6.5 10.5 6.5C9.74 6.5 9.02 6.1 8.54 5.42C8.07 4.74 7.89 3.85 8.07 3L12.93 3C13.11 3.85 12.93 4.74 12.46 5.42ZM12.83 2.5L8.17 2.5C7.81 2.51 7.51 2.12 7.5 1.63L7.5 1.54C7.51 1.09 7.76 0.72 8.09 0.68L12.76 0.01C12.94 -0.02 13.13 0.05 13.27 0.22C13.41 0.38 13.5 0.62 13.5 0.87L13.5 1.63C13.49 2.12 13.19 2.51 12.83 2.5Z"/>
+</svg>