Add userData to book request

flights.rst

@@ -991,7 +991,6 @@ Response
         from the traditional book response - please refer to the book response
         specifications for detailed information.
 
-
 Request
 =======
 
@@ -1003,6 +1002,7 @@ Request
         - **billingInfo** (:ref:`Flight_Contact`) -- billing info for ticket creation
         - **contactInfo** (:ref:`Flight_Contact`) -- contact info for ticket creation
         - **persons** (:ref:`Passenger` *\[ \]*) -- the list of passengers
+        - **userData** (:ref:`User_Data`) -- information about the end user
 
 .. _Flight_Contact:
 
@@ -1069,6 +1069,16 @@ Document
         - **issueCountry** (*String*) -- two letter code of issuing country
         - **type** (*String*) -- one of :ref:`DocumentTypes`
 
+.. _User_Data:
+
+User Data
+---------
+    :JSON Parameters:
+        - **ip** (*String*) -- the end user's IP address, e.g. ``12.123.45.67.``
+        - **browser_agent** (*String*) -- the end user's browser agent based on
+          the User-Agent HTTP header, e.g. 
+          ``Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20100101 Firefox/21.0``
+
 Response Body
 =============