Add reference files to OMC CI

[casella]

Currently, we test PowerGrids on the OMC continuous integration infrastructure, but we do not have reference files. We should add them now, for regression testing between PowerGrids 1.0.2 and PowerGrids 2.0.0 and for testing with the new backend.

1. Simulate all models of 1.0.2 with output filter port.v|port.i|omega
2. Load them as references for 1.0.2. This helps for regression testing when using the new backend, which still doesn't work with 2.0.0
3. Load them as references for 2.0.0. Check there are no regressions for models that already existed in 1.0.2
4. Once it is sure there are no regressions between 1.0.2 and 2.0.0, simulate all models of 2.0.0 with output filter port.v|port.i|omega and generate reference results for 2.0.0
5. Load them as references for 2.0.0, replacing the ones for 1.0.2