* changes for retrofitting
* changed Snakefile to work with new pypsa-eur version, change solve_network.py to clip also n.generators_t.p_min_pu
* removed retrofitting data files
These are different for residential and services demand.
Also include Snakefile in config files copied for each run.
Use gurobi settings from gurobi support for speed.
Commented out settings for testing randomness for noise.
These are specified in data/heat_load_profile.csv.
The resulting heat_demand df has MultiIndex columns, where the first
level is ["sector use"], and the second level level is nodes.
Before both initial SOC and final SOC were set to be zero, which
prevents synthetic fuel transfer over the year boundary, and prevents
the use of fossil fuels for non-zero CO2 scenarios.
Now done properly with cyclic Store (prevents accumulation of fossil
fuels as a form of sequestration) and Generator (to imitate fossil
fuel extraction).
