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/police.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" id="police" xmlns="http://www.w3.org/2000/svg" width="15" height="15" viewBox="0 0 15 15">
+  <path id="rect4718" d="M5.5,1L6,2h5l0.5-1H5.5z M6,2.5v1.25c0,0,0,2.75,2.5,2.75S11,3.75,11,3.75V2.5H6z M1.9844,3.9863&#xA;&#x9;C1.4329,3.9949,0.9924,4.4485,1,5v4c-0.0001,0.6398,0.5922,1.1152,1.2168,0.9766L5,9.3574V14l5.8789-6.9297&#xA;&#x9;C10.7391,7.0294,10.5947,7,10.4414,7H6.5L3,7.7539V5C3.0077,4.4362,2.5481,3.9775,1.9844,3.9863z M11.748,7.7109L6.4121,14H12&#xA;&#x9;V8.5586C12,8.2451,11.9061,7.9548,11.748,7.7109z"/>
+</svg>