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/jewelry-store.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" id="jewelry-store" xmlns="http://www.w3.org/2000/svg" width="15" height="15" viewBox="0 0 15 15">
+  <path d="M12,8.5c0,2.4853-2.0147,4.5-4.5,4.5S3,10.9853,3,8.5c0-1.8483,1.1164-3.4329,2.7099-4.1255l0.1761,0.137l0.7739,0.6019&#xA;&#x9;C5.1366,5.4922,4,6.8611,4,8.5C4,10.4299,5.5701,12,7.5,12S11,10.4299,11,8.5c0-1.6389-1.1366-3.0078-2.6599-3.3866l0.95-0.7388&#xA;&#x9;C10.8836,5.0672,12,6.6517,12,8.5z M7.5,4.5L10,2.5555L9,1H6L5,2.5555l1.5,1.1667L7.5,4.5z"/>
+</svg>