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/car_parked.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="M11 5C11.55 5 12 5.45 12 6L12 9L11 9L11 10C11 10.55 10.55 11 10 11C9.45 11 9 10.55 9 10L9 9L6 9L6 10C6 10.55 5.55 11 5 11C4.45 11 4 10.55 4 10L4 9L3 9L3 6C3 5.45 3.45 5 4 5L4.89 2.34C4.96 2.14 5.15 2 5.36 2L9.64 2C9.85 2 10.04 2.14 10.11 2.34L11 5ZM5 8C5.55 8 6 7.55 6 7C6 6.45 5.55 6 5 6C4.45 6 4 6.45 4 7C4 7.55 4.45 8 5 8ZM5 5L10 5L9.38 3L5.62 3L5 5ZM10 8C10.55 8 11 7.55 11 7C11 6.45 10.55 6 10 6C9.45 6 9 6.45 9 7C9 7.55 9.45 8 10 8ZM11.5 12L11 11L13 11L14 13L1 13L2 11L4 11L3.5 12L11.5 12Z"/>
+</svg>