Get the second cross

[lymacasm]

Write a method in the Solve class in solver.py that implements the algorithm used to get the cross on the bottom of the cube. The method should first check that there are no moves in the moves queue, self.Moves. If the queue contains moves, the method should pop, and return the first move of the queue. Else, if the queue is empty, the method should fill the queue with the moves required to implement the algorithm for the cross.