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/lounger.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="M14.71 3.29C15.07 3.65 15.1 4.22 14.79 4.61L14.71 4.71L11 8.41L11 12L9 12L9 9L2 9L2 12L0 12L0 8C0 7.49 0.39 7.06 0.88 7.01L1 7L9.58 7L13.29 3.29C13.68 2.9 14.32 2.9 14.71 3.29Z"/>
+</svg>