add licence header

Author: Scottmitch

examples/src/test/java/org/reactivestreams/example/unicast/AsyncRangePublisherTest.java

@@ -1,3 +1,6 @@
+/***************************************************
+ * Licensed under MIT No Attribution (SPDX: MIT-0) *
+ ***************************************************/
 package org.reactivestreams.example.unicast;
 
 import org.reactivestreams.Publisher;