make statements-babel.sty

[kohlhase]

sTeX is starting to be used outside Jacobs. So we need multi-language support. This is most conspicuous in the statements package, which generates keywords like Lemma and Conjecture, which are language-dependent. The statements package already makes these configurable, but they should be configurable with babel support.

So I guess the right thing to be would be to do two things:

1. define language-dependent default mapping to the configuration keywords: \def\st@theorem@kw{\iflanguge{german}Satz\fi\iflanguage...}. This should probably only be done when babel is loaded or if the babel option is given. I am not sure what the right user interface is here.
2. have a user-visible configuration macro with which the user can override this default. E.g. \STconfigureKW{conjecture}{Vermutung}.

I will only implement this (help wanted), when I understand what we need here completely. So please give me feedback.

Maybe we should think about multi-lingual extension of sTeX as a whole. There may well be other places, where babel support is needed.

[tpfeiffer]

As I understand it, the \sref macro also puts the name of the referenced object there, like "equation (2.1)" or "section 3". (Besides not knowing if this is good to have at all,) These strings would also have to be translated.