[Seaside] Localization

[Brent Pinkney]

Hi Avi,

> Certainly, there's a need for good localization support for Seaside.
> It's been on my todo list for quite a while... :/

I have achieved quite good localisation in Seaside to support per-session  
translation.

Basically, I followed the resumable exception strategy used by  
WACurrentSession: I introduced a CurrentTranslator exception which is  
signalled in String>>#translated.

If uncaught this excpetion's #defaultAction is to return  
"NaturalLanguageTranslator current" as in the stock 3.8 image. This makes  
it fully compatible.

I have then modified a few methods in Seaside to catch this exception and  
resume with the WASession's preferred translator. Determining the current  
translator is application specific.

Let me know if you are interested in details - it should probably be  
generalised to catch the current preferred Locale - the  
NaturalLanguageTranslator is a function of a Locale.

Regards

Brent