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/police_officer.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="M11 8L11 14.5C11 14.5 11 14.5 11 14.5C11 14.78 10.77 15 10.5 15L5 14.98L11 8ZM4 14.5L4 8.5C4 8.22 4.22 8 4.5 8L9.5 8L4 14.5ZM10 4C10.02 4.09 10.03 4.41 10.03 4.97C10.03 4.97 10.03 4.97 10.03 4.97C10.03 6.37 8.9 7.5 7.5 7.5C7.48 7.5 7.47 7.5 7.45 7.5C6.08 7.47 4.99 6.34 5.02 4.97L5.02 4.97C5.03 4.42 5.05 4.1 5.07 4L7.5 5L10 4ZM11 2.75L7.5 4.25L4 2.75L4 1C4.92 0.95 5.59 0.87 6 0.75C6.41 0.63 6.9 0.38 7.46 0C8.04 0.37 8.55 0.62 9 0.75C9.45 0.88 10.11 0.96 11 1L11 2.75ZM8.5 2.01C8.44 1.94 8.38 1.88 8.3 1.82C7.75 1.38 6.94 1.46 6.5 2.01L6.5 2.01L7.11 2.77C7.13 2.8 7.16 2.83 7.19 2.85C7.4 3.02 7.72 2.99 7.89 2.77L8.5 2.01Z"/>
+</svg>