Documentation: Add link to "by-example" section to primary navigation

Author: amotl

docs/index.rst

@@ -160,6 +160,11 @@ The DB API driver and the SQLAlchemy dialect support :ref:`CrateDB's data types
 please consult the :ref:`data-types` and :ref:`SQLAlchemy extension types
 <using-extension-types>` documentation pages.
 
+.. toctree::
+    :maxdepth: 2
+
+    data-types
+
 Examples
 ========
 
@@ -173,6 +178,11 @@ Examples
   connect to CrateDB using `pandas`_, and how to load and export data.
 - The `Apache Superset`_ and `FIWARE QuantumLeap data historian`_ projects.
 
+.. toctree::
+    :maxdepth: 2
+
+    by-example/index
+
 
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