Geomagnetic field effects for muon analysis

[burmist-git]

Include effect of bending of the muon trajectory due to geomagnetic field Eqs. 49-51 of [RD] (https://iopscience.iop.org/article/10.3847/1538-4365/ab2123/pdf).

[maxnoe]

I think at the moment, we only have the B-Field in the simulations.

@kosack I think this should be added to the SubarrayDescription?