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/pharmacy.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.2" baseProfile="tiny" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 50 50" overflow="inherit">
+  <path d="M39.35 17h-28.95c-5.17 0 -9.4 3.64 -9.4 8.5c0 4.86 4.23 8.5 9.4 8.5h28.95c5.17 0 9.4 -3.64 9.4 -8.5c0 -4.86 -4.23 -8.5 -9.4 -8.5zm0 15h-14.35v-13h14.36c3.81 0 6.93 2.92 6.93 6.5s-3.12 6.5 -6.93 6.5z"/>
+</svg>