Inconsistencies in the cross functions #280

1. The basic cross function is crossVirginQueen. Here, we provide drones and nFathers. If we have:

• 1 virgin queen, we do: fathers <- selectInd(pop = drones, nInd = n, use = "rand")
• multiple virgin queens, we do: fatherGroups <- pullDroneGroupsFromDCA(DCA = drones,n = nVirginQueen,nFathers = nFathers)

Note that the first one doesn't "kill" the drones, while the second one does.

2. In the crossColony, we don't select any fathers, but instead, just pass the drones to crossVirginQueen.

3. In the crossColonies, we again sample father groups, which is then again done by crossColony that we call in here
   fatherGroups <- pullDroneGroupsFromDCA(DCA = drones, n = nCol, nFathers = nFathers, removeFathers = removeFathers)
   Also, note that here we pass the argument removeFathers, where in the crossVirginQueen we don't.

Almost all of this will be fixed by collapsing the functions, but just so that we are aware of what is hapenning.