Added CC license image.

Fixes #385

README.adoc

@@ -31,9 +31,6 @@ We are glad you want to contribute to the Arduino Reference: that's the best way
 
 Your contribution is adding or modifying existing code or full descriptions, please always refer to an existing issue or open a new one before contributing. 
 
-Please note that your contribution to the Arduino Reference is licensed under a Creative Commons Attribution-Share Alike 3.0 License. see https://creativecommons.org/licenses/by-sa/3.0/
-
-
 === Folder Structure
 [source]
 ----
@@ -56,3 +53,9 @@ reference-en
 ----
 
 Within the Language folder, the file tree follows the same structure as in the link:https://www.arduino.cc/reference/en[Arduino Reference webpage]
+
+=== License
+
+Please note that your contribution to the Arduino Reference is licensed under a Creative Commons Attribution-Share Alike 3.0 License. see https://creativecommons.org/licenses/by-sa/3.0/
+
+image:https://i.creativecommons.org/l/by-sa/3.0/88x31.png[Creative Commons License, title="Creative Commons License"] This work is licensed under a link:https://creativecommons.org/licenses/by-sa/3.0/deed.en[Creative Commons Attribution-ShareAlike 3.0 Unported License].