Add Licensing information to README

Docker-DCO-1.1-Signed-off-by: Vincent Mayers vince.mayers@gmail.com (github: vincentmayers)
[solomon@docker.com: rephrased commit message and transcribed signoff]
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)

README.md

@@ -190,3 +190,9 @@ It is your responsibility to ensure that your use and/or transfer does not
 violate applicable laws. 
 
 For more information, please see http://www.bis.doc.gov
+
+
+Licensing
+=========
+Docker is licensed under the Apache License, Version 2.0. See LICENSE for full license text.
+