Update README.md

Dirk-- · Dirk-- · commit f1a2dd523d1d · 2015-01-27T18:21:44.000+01:00
wiki Link added
diff --git a/README.md b/README.md
@@ -10,3 +10,5 @@ Upon the first discussion, this would be something like:
 * published scale
 * National number (prefixed by country code?)
 * National name
+
+More details at http://wiki.openseamap.org/wiki/OpenSeaMap-dev:Catalogue_of_INT_Charts
