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/passport_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="M8.05 3.5L12.95 3.5C12.98 3.66 13 3.83 13 4C13 5.38 11.88 6.5 10.5 6.5C9.12 6.5 8 5.38 8 4C8 3.83 8.02 3.66 8.05 3.5ZM12.79 3L8.21 3L6.25 3C6.11 3 6 2.89 6 2.75C6 2.6 6.09 2.46 6.23 2.4L8 1.58L8 0.67C8 0.39 8.22 0.17 8.5 0.17C8.54 0.17 8.59 0.17 8.63 0.18C10.69 0.73 12.15 1 13 1C13.19 1 13.36 1 13.5 1L13.5 1C13.78 1 14 1.22 14 1.5L14 2.5C14 2.78 13.78 3 13.5 3L12.79 3ZM14 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 13.5ZM1.5 1L4.5 1C4.78 1 5 1.22 5 1.5L5 5.5C5 5.78 4.78 6 4.5 6L1.5 6C1.22 6 1 5.78 1 5.5L1 1.5C1 1.22 1.22 1 1.5 1ZM3 2C2.45 2 2 2.45 2 3C2 3.55 2.45 4 3 4C3.55 4 4 3.55 4 3C4 2.45 3.55 2 3 2Z"/>
+</svg>