Don't read docs on Github

Author: gaearon

doc/README.md

@@ -0,0 +1,7 @@
+**These are not the docs you are looking for!**
+
+This folder contains the docs for an unreleased version.  
+They may be incomplete, outdated, or outright misleading.  
+Read the docs on the official React Router website instead:
+
+http://rackt.github.io/react-router