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/disc_golf_basket.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="M7 14L1.72 14L0.07 11.26C-0.07 11.02 0.01 10.71 0.24 10.57C0.48 10.43 0.79 10.51 0.93 10.74L2.28 13L5.76 13C3.35 11.13 2.1 8.11 2.01 4L2 4C1.72 4 1.5 3.78 1.5 3.5C1.5 3.22 1.72 3 2 3L13 3C13.28 3 13.5 3.22 13.5 3.5C13.5 3.78 13.28 4 13 4L12.99 4C12.9 8.11 11.65 11.13 9.24 13L12.72 13L14.07 10.74C14.21 10.51 14.52 10.43 14.76 10.57C14.99 10.71 15.07 11.02 14.93 11.26L13.28 14L8 14L8 15L7 15L7 14ZM7 11.66L7 4L5.5 4C5.55 7.11 6.05 9.67 7 11.66L7 11.66ZM4.5 4L3.01 4C3.09 7.6 4.09 10.22 6.01 11.91C5.05 9.8 4.55 7.16 4.5 4L4.5 4ZM8 11.66C8.95 9.67 9.45 7.11 9.5 4L8 4L8 11.66L8 11.66ZM10.5 4C10.45 7.16 9.95 9.8 8.99 11.91C10.91 10.22 11.91 7.6 11.99 4L10.5 4L10.5 4ZM7.5 0C8.33 0 9 0.67 9 1.5C9 2.33 8.33 3 7.5 3C6.67 3 6 2.33 6 1.5C6 0.67 6.67 0 7.5 0Z"/>
+</svg>