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/lock.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.2" baseProfile="tiny" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 50 50" overflow="inherit">
+  <path d="M43.16 21h-2.16v-8.63c0 -5.68 -5.7 -11.37 -11.37 -11.37h-9.48c-5.67 0 -11.14 5.69 -11.14 11.37v8.63h-2.39c-0.68 0 -1.61 1.06 -1.61 1.66v25.46c0 0.6 0.93 0.88 1.61 0.88h36.55c0.68 0 1.84 -0.28 1.84 -0.88v-25.46c0 -0.6 -1.16 -1.66 -1.84 -1.66zm-13.45 24h-9.65l2.03 -9.97c-1.22 -0.87 -2.02 -2.5 -2.02 -4.11c0 -2.64 2.16 -4.89 4.83 -4.89s4.83 2.09 4.83 4.73c0 1.61 -0.8 3.43 -2.02 4.3l2.02 9.94zm4.29 -24h-18v-8.63c0 -2.58 1.69 -4.37 4.24 -4.37h9.29c2.55 0 4.47 1.79 4.47 4.37v8.63z"/>
+</svg>