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/maki/scooter.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg id="scooter" xmlns="http://www.w3.org/2000/svg" width="15" height="15" viewBox="0 0 15 15">
+  <path d="M4.908,12a1.5,1.5,0,1,1-2.816,0Zm8.65-6C13.539,6,13,6,13,6V3h.351a.282.282,0,0,0,.223-.148l.268-.536a.334.334,0,0,0,.009-.066A.25.25,0,0,0,13.6,2H13V1.7a.215.215,0,0,0-.2-.2H9.25a.25.25,0,0,0,0,.5H12V6.6L7.6,10H6V7.5A.5.5,0,0,0,5.5,7H5V5H6.75a.25.25,0,0,0,0-.5L2.266,4.034c-.006,0-.01-.007-.016-.007a.25.25,0,0,0-.25.25V4.75A.25.25,0,0,0,2.25,5H3V7H2.5A1.538,1.538,0,0,0,1,8.5v2a.472.472,0,0,0,.442.5C1.461,11,7.5,11,7.5,11L10,10h3.5a.472.472,0,0,0,.5-.442C14,9.539,14,6.5,14,6.5A.472.472,0,0,0,13.558,6ZM12.5,11A1.5,1.5,0,1,0,14,12.5,1.538,1.538,0,0,0,12.5,11Z"/>
+</svg>