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/window.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="M12.5 13.5L12.5 14.5L2.5 14.5L2.5 13.5L12.5 13.5zM11 2L11 6L8 6L8 2L11 2zM7 2L7 6L4 6L4 2L7 2zM7 7L7 11.5L4 11.5L4 7L7 7zM11 7L11 11.5L8 11.5L8 7L11 7zM2.5 0.5L2.5 13L12.5 13L12.5 0.5L2.5 0.5z"/>
+</svg>