[Zope] Keep track of language.

[Chris McDonough]

> The CoreSession product currently supports two SessionDataManager
> types, a RAM session data manager that keeps the session
> information in RAM (i.e. no database)
> and an external SessionDataManager that stores the
> session information in ZODB.

Technically, this isn't correct.  Although a RAM-based ("internal") session
data manager stores session data in RAM, it uses a custom RAM-based ZODB
storage to do so.  So even if you're using an internal data container,
you're using the ZODB (although chances are you don't know it, and don't
care).

There's nothing preventing someone from writing a RDBMS-backed session data
manager, however, as Dieter states.  Nobody has done it yet, however.