Be more clear about licensing. https://www.w3.org/Bugs/Public/show_bu…

…g.cgi?id=24893

README.md

@@ -0,0 +1,19 @@
+resources.whatwg.org
+====================
+
+Contributors
+------------
+
+* Anne van Kesteren
+* Domenic Denicola
+* Janessa Det
+* Matthew Raymond
+* Robbert Broersma
+* Simon Pieters
+
+License
+-------
+
+[![CC0](http://i.creativecommons.org/p/zero/1.0/80x15.png)](http://creativecommons.org/publicdomain/zero/1.0/)
+To the extent possible under law, the contributors have waived all copyright and related
+or neighboring rights to this work.