Clarify the documentation on reference stealing

Provide an example usage pattern for reference stealing functions.
This way the user (hopely) sees more clearly how the reference
stealing functions are meant to be used.

doc/apiref.rst

@@ -154,9 +154,31 @@ Normally, all functions accepting a JSON value as an argument will
 manage the reference, i.e. increase and decrease the reference count
 as needed. However, some functions **steal** the reference, i.e. they
 have the same result as if the user called :cfunc:`json_decref()` on
-the argument right after calling the function. These are usually
-convenience functions for adding new references to containers and not
-to worry about the reference count.
+the argument right after calling the function. These functions are
+suffixed with ``_new`` or have ``_new_`` somewhere in their name.
+
+For example, the following code creates a new JSON array and appends
+an integer to it::
+
+  json_t *array, *integer;
+
+  array = json_array();
+  integer = json_integer(42);
+
+  json_array_append(array, integer);
+  json_decref(integer);
+
+Note how the caller has to release the reference to the integer value
+by calling :cfunc:`json_decref()`. By using a reference stealing
+function :cfunc:`json_array_append_new()` instead of
+:cfunc:`json_array_append()`, the code becomes much simpler::
+
+  json_t *array = json_array();
+  json_array_append_new(array, json_integer(42));
+
+In this case, the user doesn't have to explicitly release the
+reference to the integer value, as :cfunc:`json_array_append_new()`
+steals the reference when appending the value to the array.
 
 In the following sections it is clearly documented whether a function
 will return a new or borrowed reference or steal a reference to its