NEW CASTLE, Del. (AP) — A neat stack of 79-cent bananas and rows of colorful fruit flanked the bilingual alternative pop band Luna Luna as they performed for a small audience at a Latino grocery store in northern Delaware. The show was part of the monthly Mercadito sessions put on by the Fiesta Fresh Market, a family-owned store in the Philadelphia metro-area city of New Castle, far away from the massive music industry hubs typically associated with artistic opportunity and exposure. But the