allow for multiple use_in_calib parameters

[sebkopf]

create all permutations of the model and use_in_calib parameters to allow easier evaluation of fits across different calibration ranges. Probably requires a new column to capture what the range is (either the expression or a name, similar to how the model_name works). Having this additional column would be a significant addition at the basic level of the regression machinery. Consider carefully what this means for regressions, range predictions and in_range plotting.