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/telescope.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="M8.34 6.15L11.96 14.3C12.07 14.55 11.96 14.84 11.7 14.96C11.45 15.07 11.16 14.96 11.04 14.7L9.84 12L5.16 12L3.96 14.7C3.84 14.96 3.55 15.07 3.3 14.96C3.04 14.84 2.93 14.55 3.04 14.3L6.23 7.13L4.49 7.94L3.22 5.23L10.01 2.06L11.28 4.77L8.34 6.15ZM7.5 6.73L5.6 11L9.4 11L7.5 6.73ZM10.26 1.39L12.98 0.12L14.67 3.75L11.95 5.02L10.26 1.39ZM0.26 7.16L2.98 5.89L3.82 7.7L1.1 8.97L0.26 7.16Z"/>
+</svg>