Add an option for CO2 setpoint to the honeybee_energy.load Setpoint class

[chriswmackey]

I sense that implementing this will be very similar to how humidistats are currently implemented for rooms that need tight humidity controls. We'll basically just write a ZoneContol:ContaminantController object in similar to how the ZoneControl:Humidistat is written in. More information about the use cases of this can be found here:

https://discourse.pollination.cloud/t/missing-parameters-in-rhino-gh-plugin/3565/18

[chriswmackey]

Just a note that EnergyPlus also needs you to add the following text in order for it to be able to perform the CO2 calculation:

ZoneAirContaminantBalance,
    Yes,                     !- Carbon Dioxide Concentration
    Outdoor CO2 Level,       !- Outdoor Carbon Dioxide Schedule Name
    No;                      !- Generic Contaminant Concentration

Schedule:Constant,
    Outdoor CO2 Level,       !- Name
    ,                        !- Schedule Type Limits Name
    420;                     !- Hourly Value

More information on getting this all to happen can be found here along with a sample GH file:

https://discourse.ladybug.tools/t/atmospheric-indoor-climate-in-ppm/24833