add reference to YourKit

README.textile

@@ -16,6 +16,15 @@ Version
  1.0.0                       | 0.16.2 -> 0.19.0   
 
 
+Thanks
+-------------
+YourKit supports IK Analysis for ElasticSearch project with its full-featured Java Profiler.
+YourKit, LLC is the creator of innovative and intelligent tools for profiling
+Java and .NET applications. Take a look at YourKit's leading software products:
+<a href="http://www.yourkit.com/java/profiler/index.jsp">YourKit Java Profiler</a> and
+<a href="http://www.yourkit.com/.net/profiler/index.jsp">YourKit .NET Profiler</a>.
+
+
 Install
 -------------
 you can download this plugin from RTF project(https://github.com/medcl/elasticsearch-rtf)