Cut hens in half, remove backbones, and wash and pat dry. Season with salt and pepper. Combine oil, garlic, rosemary, and thyme. Arrange hens in a shallow dish and pour oil mixture over them. Cover, let marinate 30 minutes or refrigerate overnight. Arrange hens on broiler rack, brush with marinade, and broil 4 inches from heat for 20 minutes or until done, turning several times and brushing with marinade. Remove hens. With skin side up, spread with mustard, sprinkle with bread crumbs, and broil 2 minutes or until bread crumbs are golden.