Docs: Restructuring and new layout

This patch implements a set of user-experiences aimed
changes.It modifies the documentation structure and
switches to a more reactive design for the rtd theme.

* The documentation layout has been redesigned to be more
  intuitive,easier to maintain and and scale.
* The landing page introduces a new dashboard.
* Introduced dedicated space for release documents, and
  changelog has been modified to directly source content
  from referenced documents.
* Added quick-link navigation for items that need emphasis.
* Relevant design documents can now be grouped in suf-folders.
* There is dedicated space for custom platform, and third
  party tools documents.
* Wildcard and regex matching has been introduced to indexes.

Change-Id: Ib02d17d5d26187d397ba17317788cf2a01401b07
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
diff --git a/docs/design_documents/source_structure.rst b/docs/design_documents/source_structure.rst
index 66ca057..b22be0b 100644
--- a/docs/design_documents/source_structure.rst
+++ b/docs/design_documents/source_structure.rst
@@ -6,7 +6,7 @@
 :Contact: tf-m@lists.trustedfirmware.org
 
 .. note::
-  Refernce the document :doc:`Glossary </docs/glossary>` for terms and
+  Refernce the document :doc:`Glossary </docs/reference/glossary>` for terms and
   abbreviations.
 
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