First stub for modstd support for modules

[HechtiDerLachs]

I needed this for a project with @simonfelten, so this is an effort to bring Singular's ModStd to the OFPModules in Oscar.
I will try to do everything in parallel to what we have for ideals. I think, it would be nice if throughout the next weeks we could discuss how such functionality could be integrated into Oscar, even if not user-facing for the moment.

ping @jankoboehm , @wdecker

[HechtiDerLachs]

I consulted with @JohnAAbbott about his "dodgy_mode". This PR now needs to be run with this one on AA. Up to now it is a suggestion as to how we might integrate this functionality. Feel free to have a look!

[HechtiDerLachs]

@ederc raises the question how we want to cache dodgy stuff. In this PR I introduce an extra cache for "dodgy groebner bases", but maybe this is not what we want to do?

@YueRen suggests that the log allows the user to track dodgy intermediate results and to use only one cache. @ederc agrees and suggests that one may still add a flag to the data type for the GB to keep the information whether it was obtained in a dodgy way.

In general people are in favor of not introducing parallel caching structures.