Set `gn_forecasts(*, node, timeseries)` tells for which grid/flow/restype, node and timeseries combinations use forecasts and by default includes everything.

See: #99

#82: All hard-coded *elec* grids have been removed and replaced by looping/summing over *gn* instead. This fix should work as long as no *node* belongs to multiple *grids*, which I think is already ill-advised (or even forbidden?).

Also a minor speedup for setting model dimension (set `msft` etc.)

Changed behaviour of `mSetting` 't_perfectForesight' so that it’s defined from zero (not after 't_jump')

The setting does not have any effect if 't_perfectForesight' is less than 't_jump'.

Parameter `p_msft_probability` was not updated after scenario reduction.

Default is zero, can be changed via command line parameter --debug=[0|1|2].

Use --input_dir=<path> and --output_dir=<path>. Defaults are ./input and ./output, respectively.