Convergence of large outflows from small Basins

[visr]

If you have a small Basin with e.g. a large infiltration, the model is not very stable. We need to build a test model for this case to make sure it is able to handle such a case well. In principle we use a reduction_factor to reduce the infiltration, but for sufficiently large outflows it will step over this smooth landing within one timestep. We need to look into this case to understand the behavior, and how it behaves with both adaptive and fixed timestepping, under different solvers. Perhaps we need to use better tolerances or error norms to handle these cases better.

Related to #1406.