add license for tutorial wiki data (#8944)

* add license for tutorial wiki data

* tweaks

Author: clintropolis

LICENSE

@@ -314,3 +314,14 @@ SOURCE/JAVA-CORE
     This product uses a smear function adapted from MurmurHash3, written by Austin Appleby who has placed
      MurmurHash3 in the public domain (https://github.com/aappleby/smhasher/blob/master/src/MurmurHash3.cpp).
       * processing/src/main/java/org/apache/druid/query/groupby/epinephelinae/Groupers.java
+
+
+Creative Commons Attribution-ShareAlike 3.0 Unported License
+================================
+
+SOURCE/JAVA-CORE:
+    This product bundle example data collected from the Wikipedia edit stream API, the text content of which is
+     copyright by Wikipedia editors and contributors and is available under the Creative Commons Attribution-ShareAlike
+     3.0 Unported License. For details, see licenses/src/CC-BY-SA.txt. This content is NOT part of the source code and
+     is only used for example and tutorial purposes.
+      * examples/quickstart/tutorial/wikiticker-2015-09-12-sampled.json.gz