docs: Release notes for version 0.2.0

Change-Id: Ied19433005fb01dee3f182ed2848cb8cf5ab37b0
Refs: #1714
diff --git a/docs/README.rst b/docs/README.rst
index d35e397..437649d 100644
--- a/docs/README.rst
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@@ -29,6 +29,10 @@
 performance.  The intention is that performance optimizations are one type of experiments
 that developers can conduct by trying out different data structures and different
 algorithms; over time, better implementations may emerge within the same design framework.
+To facilitate such experimentation with the forwarder, the NFD team has also written a
+`developer's guide <http://named-data.net/wp-content/uploads/2014/07/NFD-developer-guide.pdf>`_,
+which details the current implementation and provides tips for extending all aspects of
+NFD.
 
 NFD will keep evolving in three aspects: improvement of the modularity framework, keeping
 up with the NDN protocol spec, and addition of other new features. We hope to keep the