docs: improve formatting and document structure

Change-Id: I530d58f2700eb264855843021db32f568d373a1d
diff --git a/docs/releases.rst b/docs/releases.rst
index 39b1403..96ed2ea 100644
--- a/docs/releases.rst
+++ b/docs/releases.rst
@@ -1,5 +1,5 @@
 NLSR Versions
-+++++++++++++
+=============
 
 .. toctree::
    :glob: