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/parking-garage.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" id="parking-garage" xmlns="http://www.w3.org/2000/svg" width="15" height="15" viewBox="0 0 15 15">
+  <path d="M10.5,10.14c-0.6637,0.4788-1.4732,0.7121-2.29,0.66h-1.9V14h-1.9V5h3.92&#xA;&#x9;c0.7801-0.0414,1.5484,0.2041,2.16,0.69c0.5779,0.5595,0.875,1.3483,0.81,2.15C11.4042,8.6892,11.1088,9.5388,10.5,10.14z M9,6.9&#xA;&#x9;C8.711,6.6881,8.3579,6.5822,8,6.6H6.31v2.65H8c0.3612,0.0191,0.717-0.0947,1-0.32c0.2559-0.2675,0.3867-0.6308,0.36-1&#xA;&#x9;C9.4072,7.5493,9.274,7.1684,9,6.9z M14.41,4.21c0.114-0.2486,0.007-0.5427-0.24-0.66L7.5,0.45l-6.71,3.1&#xA;&#x9;C0.5387,3.666,0.429,3.9637,0.545,4.215C0.661,4.4663,0.9587,4.576,1.21,4.46l0,0L7.5,1.55l6.29,2.9&#xA;&#x9;c0.2486,0.114,0.5427,0.007,0.66-0.24H14.41z"/>
+</svg>