BUG Satisfy the API contract - always return SS_List instance.

Currently returning null in some situations.
Merge pull request #152 from mateusz/return-list-bug

BUG Satisfy the API contract - always return SS_List instance.
Removed testLocalePersistsInAllPageTypes()

Doesn't respect custom business logic such as
validate() methods denying page creation to certain
users, or page creation on the root level.
The test doesn't add a whole lot of value,
since the baseline translation creation doesn't
really differ between page types.