Investigate alternative solvers

[ekkea]

we are looking for:

• better performance, specifically better handling of binary variables
• proper multi-threading support
• model analytics in regards to complexity, precision ...
• ???

[t0mas]

Consider HiGHS https://highs.dev/ as one of the candidates.

While working on ways to translate the optimizer result to control actions I tested a few model variations with extra binary parameters and longer time series. CBC was significantly slower than HiGHS on those things. Haven't done a good documented comparison of the two solvers yet with the existing model.