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/hospital.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" id="hospital" xmlns="http://www.w3.org/2000/svg" width="15" height="15" viewBox="0 0 15 15">
+  <path id="rect4194" d="M7,1C6.4,1,6,1.4,6,2v4H2C1.4,6,1,6.4,1,7v1&#xA;&#x9;c0,0.6,0.4,1,1,1h4v4c0,0.6,0.4,1,1,1h1c0.6,0,1-0.4,1-1V9h4c0.6,0,1-0.4,1-1V7c0-0.6-0.4-1-1-1H9V2c0-0.6-0.4-1-1-1H7z"/>
+</svg>