Italian crescent casserole

1 pound ground Italian sausage
1 small onion, diced
2 cloves garlic, minced
1 can (8 ounces) tomato sauce
1 can (14.5 ounces) diced tomatoes, drained
1 teaspoon dried basil
1 teaspoon dried oregano
Salt and pepper to taste
1 tube (8 ounces) refrigerated crescent roll dough
2 cups shredded mozzarella cheese

Instructions: