Six years after his death, Prince’s estate has finally been legally settled. “We are free at last, thank God almighty, we are free,” Sharon Nelson, Prince’s sister, said to CBS Minnesota. “It’s been a long, long grueling six years.” Prince’s estate, valued at $156.4 million, will be split between the musician’s three eldest siblings and Primary Wave, a private music publishing company which already bought out the stakes of three other heirs. “Our goal is to work collaboratively with them to continue to build and to grow Prince’s legacy as a 50% owner,” said Primary Wave’s attorney, Eric Magnus…