add db coll section

Author: shuangela

source/databases-collections

@@ -0,0 +1,11 @@
+.. _kotlin-sync-db-collections:
+
+=========================
+Databases and Collections
+=========================
+
+.. contents:: On this page
+   :local:
+   :backlinks: none
+   :depth: 2
+   :class: singlecol

source/index.txt

@@ -15,6 +15,7 @@
 
    Getting Started </get-started>
    Connect </connect>
+   Databases & Collections </databases-collections>
    CRUD Operations </crud>
    Aggregation </aggregation>
    Builders </builders>
@@ -56,6 +57,12 @@ Connect to MongoDB
 Learn how to create and configure a connection to a MongoDB deployment
 in the :ref:`kotlin-sync-connect` section.
 
+Databases and Collections
+-------------------------
+
+Learn how to interact wth MongoDB databases and collections in the
+:ref:`kotlin-sync-db-collections` section.
+
 Read and Write Data
 -------------------