Her business plan didn’t include cancer. Misty Russell, however, hardly let the disease slow her down in operating and expanding her downtown Roseburg business. She had a double mastectomy Sept. 7 and was back to work six days later. Russell, 41, is the owner of Brix Grill Chill Gathering, an eatery, lounge and event center. She described returning to work as part of her recovery and healing. “I have goals and dreams,” she said. “There are some things we’d like to get to, and I just have no time for this cancer business.” She also had no desire to sit …