DOCSP-38145 mongoimport default db (#138)

* DOCSP-38145 mongoimport default db

* fix ref

* add note on non-existent db

Author: ajhuh-mdb

source/includes/fact-default-no-db-or-uri.rst

@@ -0,0 +1,4 @@
+If you don't specify a database with the :option:`--db <mongoimport --db>` or 
+:option:`--uri <mongoimport --uri>` option, ``mongoimport`` uses the 
+``test`` database by default. If the ``test`` database doesn't exist, 
+``mongoimport`` creates the database.

source/mongoimport.txt

@@ -214,7 +214,11 @@ Options
    .. code-block:: none
 
       --uri "mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]"
-   
+
+   .. note:: 
+
+      .. include:: /includes/fact-default-no-db-or-uri.rst
+
    .. include:: /includes/extracts/uri-positional-mongoimport.rst
 
    For information on the components of the connection string, see
@@ -451,6 +455,9 @@ Options
 
    .. include:: /includes/extracts/uri-used-with-db.rst
 
+   .. note:: 
+
+      .. include:: /includes/fact-default-no-db-or-uri.rst
 
 .. option:: --collection=<collection>, -c=<collection>