Fair workload

Distribute number of shifts fairly over a specific set of employees and a specific set of shifts during a specific period.

fairness
{
  "fairnessBuckets": [
    {
      "employees": [
        "John",
        "Andrew"
      ],
      "shifts": [
        "shift1",
        "shift2"
      ],
      "period": {
        "from": "2020-01-01",
        "to": "2020-01-15"
      }
    }
  ]
}