SAN FRANCISCO (AP) — Joan Quigley, the astrologer who helped determine President Ronald Reagan's schedule and claimed to have convinced him to soften his stance toward the Soviet Union, has died.The San Francisco Chronicle, quoting Quigley's sister, Ruth, said Friday Joan Quigley died Oct. 21 at her San Francisco home at the age of 87 after an unspecified illness.Nancy Reagan began consulting Quigley after the 1981 assassination attempt on her husband.