There’s an old grocery store in Detroit, Texas.  Its shelves are stocked with music.  Edith DeWitt’s dad opened the place in 1919.  His daughter has nudged aside the can goods to nourish other needs.  For 66 years she learned to play dozens of instruments so she could teach whatever her students wanted to master — piano, organ, drums, ballroom dancing, tap dancing, marimba, banjo.  She also mastered ballet, acrobatic dancing, drama and voice.  Her most important lesson?