Add links to the legacy quicktour

JAVA-1734

Author: rozza

docs/reference/content/getting-started/index.md

@@ -19,3 +19,9 @@ To help you get started with the new async driver, follow:
 
   * [Async Quick Tour]({{< ref "getting-started/async-quick-tour.md" >}})
   * [Async Admin Quick Tour]({{< ref "getting-started/async-quick-tour-admin.md" >}})
+
+
+To help you get started with the legacy `DB` and `DBCollection` API, follow:
+
+  * [Legacy Quick Tour](http://mongodb.github.io/mongo-java-driver/2.13/getting-started/quick-tour/)
+  * [Legacy Admin Quick Tour](http://mongodb.github.io/mongo-java-driver/2.13/getting-started/quick-tour-admin/)