220 config file csv - initial chem species are moved to CSV, and also specified with JSON data

[carl-drews]

my_config.json will now initialize chemical species like this JSON specifying one or more CSV files:

  "initial conditions": {
    "filepaths": ["initial_conditions.csv"],
    "data": [
      ["ENV.temperature [K]", "ENV.pressure [Pa]", "CONC.A [mol m-3]", "CONC.B [mol m-3]"],
      [200, 70000, 0.8, 0.2]
    ]
  },

Evolving conditions are also specified in the same manner:

  "evolving conditions": {
    "filepaths": [
      "conditions_Boulder.csv"
    ]
  },

The implementation provides warnings when a later condition overrides an earlier one.