DOCSP-17236 drawer pages (#120)

* added drawers for each API page

Author: kyuan-mongodb

source/api-documentation.txt

@@ -0,0 +1,15 @@
+=================
+API Documentation
+=================
+
+.. default-domain:: mongodb
+
+.. toctree::
+   :titlesonly:
+   :maxdepth: 1
+
+    Bson <http://mongodb.github.io/mongo-java-driver/4.3/apidocs/bson/index.html>
+    Core <http://mongodb.github.io/mongo-java-driver/4.3/apidocs/mongodb-driver-core/index.html>
+    Java Driver (modern API) <http://mongodb.github.io/mongo-java-driver/4.3/apidocs/mongodb-driver-sync/index.html>
+    Java Driver (legacy API) <https://mongodb.github.io/mongo-java-driver/4.3/apidocs/mongodb-driver-legacy/index.html>
+    

source/index.txt

@@ -11,7 +11,7 @@ MongoDB Java Driver
    /quick-start
    /usage-examples
    /fundamentals
-   API Documentation <http://mongodb.github.io/mongo-java-driver/4.3/apidocs/mongodb-driver-sync/>
+   /api-documentation
    /faq
    /issues-and-help
    /compatibility