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/well_pump_manual.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="M7.5 4L7.5 4L7.5 5L4 5C3 5 2 6 2 7L2 9L1.5 9C1.25 9 1 9.25 1 9.5L1 10L5 10L5 9.5C5 9.25 4.75 9 4.5 9L4 9L4 7C4 7 5.67 7 7 7L7 13L4.5 13C4.25 13 4 13.25 4 13.5L4 14L12 14L12 13.5C12 13.25 11.75 13 11.5 13L9 13L9 5L9 4C9 4 11 4 11 7C11 10 14 11 14 11L14 9.5C14 9.5 12 9 12 6C12 1 8.5 1 7.5 1C7.5 1 7.5 1 7.5 1L7.5 1C6.67 1 6 1.67 6 2.5L6 2.5C6 3.33 6.67 4 7.5 4Z"/>
+</svg>