Add basic array.array test.

tests/basics/array.py

+import array
+
+a = array.array('B', [1, 2, 3])
+print(a, len(a))
+i = array.array('I', [1, 2, 3])
+print(i, len(i))
+print(a[0])
+print(i[-1])
+
+# Empty arrays
+print(len(array.array('h')))
+print(array.array('i'))
+