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/golf.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" id="golf" xmlns="http://www.w3.org/2000/svg" width="15" height="15" viewBox="0 0 15 15">
+  <path id="path11758" d="&#xA;&#x9;M3.3999,1.1c0,0.1,0,0.2,0,0.2c0,0.4,0.3,0.7,0.7,0.7c0.3,0,0.5-0.2,0.6-0.5l0,0L4.9,1l5.6,2.3L6.6,6C6.2,6.3,6.2,6.7,6.3,7.1&#xA;&#x9;l0.9,2.1l-1.3,3.9C5.7,13.6,6.1,14,6.5,14c0.3,0,0.5-0.1,0.6-0.5l1.4-4l0.1,0.3v3.5c0,0,0,0.7,0.7,0.7s0.7-0.7,0.7-0.7V10&#xA;&#x9;c0-0.2,0-0.3-0.1-0.5L8.5,6.1l2.7-1.9c0.2-0.2,0.4-0.3,0.4-0.6s-0.2-0.5-0.4-0.6L4,0.1c-0.0878,0-0.118,0.0179-0.2001,0.1&#xA;&#x9;L3.3999,1.1z M5.5,3C4.7,3,4,3.7,4,4.5S4.7,6,5.5,6S7,5.3,7,4.5S6.2999,3,5.5,3z"/>
+</svg>