Move into formation function.

moveIntoFormation.swift

func moveIntoFormation() {

    // Loop over each unit in our Squad.
    for (i, unit) in enumerate(self.units) {
    
        // Get the vector from the formation class for that position. 
        // Just a simple accessor to the array.
        let vector = self.formation!.getVectorAtPosition(i)
        
        // Make a CGPoint from that vector, and tell the unit to walk to it.
        let position = CGPoint(x:vector.dx, y:vector.dy)
        unit.moveToPoint(position, callback: {
            // clean up post animation
        })
    }
}