add to NEWS about Queue#close

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52692 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

NEWS

@@ -95,6 +95,10 @@ with all sufficient information, see the ChangeLog file.
     Backtrace doesn't show each method (show block lines directly).
     TracePoint also ignores these calls. [Feature #11569]
 
+* Queue (Thread::Queue)
+
+  * Queue#close is added to notice a termination. [Feature #10600]
+
 * Regexp/String: Updated Unicode version from 7.0.0 to 8.0.0
 
 * Struct