Add the CHANGELOG to the documentation

documentation/changelog.rst

diff --git a/documentation/changelog.rst b/documentation/changelog.rst
new file mode 100644
index 0000000..81c924c
--- /dev/null
+++ b/documentation/changelog.rst
@@ -0,0 +1 @@
+..  include:: ../CHANGES.rst

documentation/index.rst

diff --git a/documentation/index.rst b/documentation/index.rst
index e56acd3..fbdb4ea 100644
--- a/documentation/index.rst
+++ b/documentation/index.rst
@@ -35,6 +35,12 @@
     examples
     appendix
 
+..  toctree::
+    :maxdepth: 1
+
+    Changelog <changelog>
+
+
 Indices and tables
 ==================