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/fireplace.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="M6.1 12L3.66 10.78L4.22 9.66L7.5 11.3L10.78 9.66L11.34 10.78L8.9 12L11.34 13.22L10.78 14.34L7.5 12.7L4.22 14.34L3.66 13.22L6.1 12ZM2 1L13 1C13.55 1 14 1.45 14 2L14 14L12 14L12.01 7.5C12.01 5.02 10 3 7.52 3L7.52 3C5.03 3 3.01 5.01 3.01 7.5L3 14L1 14L1 2C1 1.45 1.45 1 2 1ZM7 3.5L7.5 7L9 5L9.69 6.29C10.25 7.35 10 8.66 9.08 9.42L9.04 9.45C8.15 10.19 6.86 10.18 5.98 9.42C5.08 8.64 4.81 7.35 5.34 6.27C5.66 5.61 5.88 5.19 6 5C6.21 4.67 6.54 4.17 7 3.5Z"/>
+</svg>