Localizable space/document names

This is something for the (far) future.

When switching to Deki wiki, the Mozilla Developer Center complained that it cannot localize space names (like Special, User, Talk). Once we change the data model to support aliases, or when integrating internal URL rewrite, we could set an alias for each translation. This means that while now users go to /Main/Search?language=ro, they could go to /Principal/Cauta and end up in the romanian version of the search page.