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/bikini.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 9.5L14 11L12.53 11.74C11.01 12.5 9.6 13.48 8.37 14.64L8 15L7 15C5.68 13.68 4.15 12.57 2.47 11.74L1 11L1 9.5C3.5 10.17 5.67 10.5 7.5 10.5C9.33 10.5 11.5 10.17 14 9.5ZM7 4C6.22 5.33 5.06 6 3.5 6C1.17 6 0 4.2 0 3C0 2.2 0.39 1.2 1.17 0C3.38 0 5.46 1.02 6.82 2.76L7 3L8 3L8.18 2.76C9.54 1.02 11.62 0 13.83 0C14.61 1.2 15 2.2 15 3C15 4.2 13.83 6 11.5 6C10.03 6 8.9 5.4 8.13 4.2L8 4L7 4Z"/>
+</svg>