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/boulder3.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="M6 11.5C5.19 11.5 0 11.27 0 9.28C0 6.33 1.32 5.54 2.5 5C3.82 4.39 13.84 2.89 14.5 3.5C15.31 4.24 14.23 8.43 13 9C11.69 9.61 10.47 11.5 8.5 11.5C6.87 11.5 9.88 11.5 6 11.5z"/>
+</svg>