* [kotlin] support collectionFormat:multi
Adds "multi" support to collections.
Also changes generic lists (List<T>) to arrays. Generic lists and nested
lists can be problematic and require customized json factories. The
previous implement appeared to work because the results in the test were
LinkedHashMap with count greather than 0. The functional test has been
updated to force serialization and verify the results.
* [kotlin] Regenerate sample
* [kotlin] Update model test for Array changes
