Add Cling to the External Projects list.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143267 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html
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@@ -323,6 +323,20 @@
 </div>
 
 <!--=========================================================================-->
+<h3>Cling C++ Interpreter</h3>
+
+<div>
+
+<p><a href="http://cern.ch/cling">Cling</a> is an interactive compiler interface
+   (aka C++ interpreter). It uses LLVM's JIT and clang; it currently supports
+   C++ and C. It has a prompt interface, runs source files, calls into shared
+   libraries, prints the value of expressions, even does runtime lookup of
+   identifiers (dynamic scopes). And it just behaves like one would expect from
+   an interpreter.</p>
+
+</div>
+
+<!--=========================================================================-->
 <!-- FIXME: Comment out
 <h3>Crack Programming Language</h3>