Pure Rust Silent-OT

[robinhundt]

Our current implementation of Silent-OT uses either the bitpolymul or parts of libOTe.

I think we should remove the QuasiCyclic code with its dependency on bitpolymul and rewrite the current fast and secure codes of libOTe in Rust (no Silver). This simplifies our build, reduces our C/C++ dependencies and ideally also increases the portability of our Silent-OT implementation (open question: which portable SIMD abstraction should we use for this?)