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/osmic/photo.svg

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   version="1.1"
+   width="100%"
+   height="100%"
+   viewBox="0 0 14 14"
+   id="svg2">
+  <metadata
+     id="metadata8">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <defs
+     id="defs6" />
+  <rect
+     width="14"
+     height="14"
+     x="0"
+     y="0"
+     id="canvas"
+     style="fill:none;stroke:none;visibility:hidden" />
+  <path
+     d="M 5.5,1.5 C 4.5,1.5 4.3137629,2.0790211 4,3.25 l 6,0 C 9.6745414,2.0353719 9.4661017,1.5 8.5,1.5 z M 3,4 C 1,4 0,5 0,7 l 0,2 c 0,2 1,3 3,3 l 8,0 c 2,0 3,-1 3,-3 L 14,7 C 14,5 13,4 11,4 z M 2.5,5 C 2.7761424,5 3,5.2238576 3,5.5 3,5.7761424 2.7761424,6 2.5,6 2.2238576,6 2,5.7761424 2,5.5 2,5.2238576 2.2238576,5 2.5,5 z M 7,5 c 1.6392343,0 3,1.2621124 3,3 0,1.7082265 -1.3262712,3 -3,3 C 5.3607656,11 4,9.6785655 4,8 4,6.2324514 5.3311046,5 7,5 z M 7,6 C 5.8516949,6 5,6.7923729 5,8 5,9.2372881 5.8220339,10 7,10 8.2076271,10 9,9.2076271 9,8 9,6.8220339 8.1779661,6 7,6 z"
+     id="photo"
+     style="fill:#000000;fill-opacity:1;stroke:none" />
+</svg>