added yourkit license text

www.i2p2/pages/newdevelopers.html

@@ -20,6 +20,7 @@
     <li><a href="#making-the-results-available">Making the results available</a></li>
     <li><a href="#get-to-know-us">Get to know us!</a></li>
     <li><a href="#translations">Translations</a></li>
+    <li><a href="#tools">Tools</a></li>
   </ol>
 </div>
 
@@ -161,4 +162,17 @@
   for next steps.
 </p>
 
+<h2 id="Tools">Tools</h2>
+<p>
+I2P is OpenSource and mostly developed on tools which are OpenSource, too.<br>
+Nevertheless we got some license of the YourKit Java Profiler for free use on our 
+OpenSource I2P project. Only requirement beside being OpenSource is following
+html snippet about that piece of software. If you decide to work on profiling
+I2P source code, please get in contact with us and we manage the licenses.<br>
+YourKit is kindly supporting open source projects 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>.
+</p>
 {% endblock %}