Add back Dynare++ material that was present on the previous website

resources/index.md

@@ -139,3 +139,42 @@ Various bits of information such as [new](https://git.dynare.org/Dynare/dynare/w
 <p class="indent" markdown="1">
 <i class="icon-external-link"></i> [Old Wiki](http://www.dynare.org/DynareWiki/TableOfContents)
 </p>
+
+# <i class="icon-tool"></i> Dynare++
+Dynare++ is a set of C++ codes, originally written by Ondra Kamenik, that
+compute higher order approximations of DSGE models via a perturbation method.
+Those codes are made available both as a standalone executable program (shipped in the
+Dynare package) and via Dynare where they are used for higher order
+approximations (starting from third order).
+
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+[Solving Stochastic Dynamic Equilibrium Models: A K-order Perturbation Approach](https://www.dynare.org/assets/dynare++/k_order.pdf),
+a paper by Michel Juillard and Ondra Kamenik that describes the overall algorithm
+</p>
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+the
+[Dynare++ tutorial](https://www.dynare.org/assets/dynare++/dynare++-tutorial.pdf), that
+describes the usage of the standalone executable
+</p>
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+a description of the algorithm used for [Ramsey optimal policy in Dynare++](https://www.dynare.org/assets/dynare++/dynare++-ramsey.pdf)
+</p>
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+a description of the algorithm used for [solving the specialized Sylvester equation](https://www.dynare.org/assets/dynare++/sylvester.pdf)
+</p>
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+the internal documentation of the [numerical integration module](https://www.dynare.org/assets/dynare++/integ.pdf)
+</p>
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+the internal documentation of the [tensor library](https://www.dynare.org/assets/dynare++/tl.pdf)
+</p>
+<p class="indent" markdown="1">
+<i class="icon-document-download"></i>
+the internal documentation of the [k-order library](https://www.dynare.org/assets/dynare++/kord.pdf)
+</p>