Add attribute to Parsers to differentiate between projects

[thomas-qah]

Two types of PowerPlants are currently configured the codebase: 'normal' power plants and 'HIC' power plants. The latter are power plants that have been added for the HIC project that have their data structured differently than 'regular' power plants:

# Regular PowerPlant
- asset: PowerPlant
  parser: power_plant
  plant_type: INTERNAL_COMBUSTION
  fuel: NATURAL_GAS
  attr_set:
    power: { input: ..., gquery: ..., factor: ..., edr: ...},
    fullLoadHours: { input: ..., gquery: ..., factor: ..., edr: ...},
    marginalCosts: { input: ..., gquery: ..., factor: ..., edr: ...}

# "HIC" PowerPlant
- asset: PowerPlant
  parser: carrier_capacity
  attribute: power
  carrier: [..., ...]
  input: ...
  factor: ...

To differentiate between these PowerPlants at this moment, and possibly also in the future for other types of parsers, we could/should add a attribute to the Parser model so that we can filter between them more easily in the codebase.

A suggested attribute to add could be project, which in the case of these 'HIC' PowerPlants would have the value hic and be left blank/empty for 'regular' power plants.