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/room.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 9.02L14.91 11.98L14.97 12L15 12L7.5 15L0 12L0.05 12L0.05 12L0.09 11.98L7.5 9.02ZM7.5 10.08L2.69 12L7.5 13.92L12.31 12L7.5 10.08ZM7.25 0.1L7.25 8.5L7.26 8.56L7.26 8.58L5 9.48L5 5.51C5 5.36 4.97 5.22 4.91 5.08C4.67 4.54 4.04 4.29 3.5 4.53C2.65 4.9 2.07 5.72 2.01 6.64L2 6.82L2 10.68L0 11.48L0 3L7.25 0.1ZM7.75 0.1L15 3L15 11.48L7.74 8.58L7.75 8.54L7.75 8.54L7.75 8.5L7.75 0.1ZM9.75 4L9.75 7L12.75 8.25L12.75 5.25L9.75 4ZM4 6.75C4.28 6.75 4.5 6.97 4.5 7.25C4.5 7.53 4.28 7.75 4 7.75C3.72 7.75 3.5 7.53 3.5 7.25C3.5 6.97 3.72 6.75 4 6.75Z"/>
+</svg>