Add localization support for workflow text

[idpaterson]

The workflow already supports localizations of Wunderlist by querying the app for translations of items such as "Week" and "Assigned to Me" that are necessary for proper operation of the workflow. However, it would be nice to support localization of the additional text displayed in Alfred, such as "Create a new list with the specified name."

Since this is currently outside the scope of Alfred in general, the implementation will be mostly for the sake of experimentation. It would require revision of the keyword triggers to use script filters that return the localized text, which could decrease the flexibility of the workflow. This implementation of string formatting in localization will be helpful.