Add any_subgroup_largest pregrouping type

The any subgroup largest pregrouping attempts to make the largest possible subgroup from your friends selection. Violation to the objective is relative to the amount of friendship violations. This means that if you have 1 friend indicated, violating that friendship incurs a higher cost than if you have 2 friends and 1 is violated.

Required friendship violations are ignored. That is, when more friends are indicated than fit in the maximum group size, some violations are inevitable. These required violations are not counted in the objective.