Update the data endpoint documentation

- Add information about the 'or' and 'ornull' filter options

docs/data.rst

@@ -431,18 +431,35 @@ Query submissions with case insensitive and partial search
 
     curl -X GET https://api.ona.io/api/v1/data/22845?query={"name":{"$i":"hosee"}}
 
+Example V
+^^^^^^^
+Query submissions where age is 21 or name is hosee
+
+::
+
+    curl -X GET https://api.ona.io/api/v1/data/22845?query={"$or": [{"age": "21", "name": "hosee"}]}
+
+Example VI
+^^^^^^^
+Query submissions where car is honda or is null
+
+::
+
+    curl -X GET https://api.ona.io/api/v1/data/22845?query={"$ornull": [{"car": "honda"}]}
 
 All Filters Options
 
-========  ===================================
-Filter    Description
-========  ===================================
-**$gt**   Greater than
-**$gte**  Greater than or Equal to
-**$lt**   Less than
-**$lte**  Less or Equal to
-**$i**    Case insensitive or partial search
-========  ===================================
+===========  ===================================
+Filter       Description
+===========  ===================================
+**$gt**      Greater than
+**$gte**     Greater than or Equal to
+**$lt**      Less than
+**$lte**     Less or Equal to
+**$i**       Case insensitive or partial search
+**$or**      Or
+**$ornull**  Or is null
+===========  ===================================
 
 Query submitted data of a specific form using date_created
 ----------------------------------------------------------