Changed input folder structure and added data for wheat, rice and corn. Also updated part of the fitting free param script while working on adding soybean.

Merge branch 'COVID19_paper' of https://gitlab.pik-potsdam.de/twist/twist-global-model into COVID19_paper

Added extra run file for the covid-19 paper, run_TWIST_covid19.py, which can be run via commandlines

re-calibrated rice and corn with alpha_s fixed to 0.1, made runs with historic importStrat activated

Fixed bug. Now the global demand curve is taking into account lowered consumption if include_consReduction = True. Before this was not properbly implemented in the funs.consumerDemandCurve

Added missing arguments q_storage_max_cons_type, q_out_offset_type which were only incorporated in the fitting_freeParam branch and not the scenario branch.

Changed scenario so that one can now chose to reduce consumption when export restrictions are active to account for direct consumption of the region that has started with an export ban. The absolute amount of consumption reduction is also reduced from the producer storage, to compensate for direct consumption.

Split production decline into two scenarios, added so that consumption can be fixed to reported values for scenarios and also the posibility for consumption decline for the scenario year

Implemented flexible consumption where the new consumption is added to the historic time series for the scenario years, and the running mean is updated during the loop and the scenario length is completely free since no historic data is needed for the scenario period.