Convert Python types to proper Python type hierarchy.

Now much more inline with how CPython does types.
diff --git a/py/objlist.c b/py/objlist.c
index 967df44..3018826 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -36,6 +36,29 @@
     print(env, "]");
 }
 
+static mp_obj_t list_make_new(mp_obj_t type_in, int n_args, const mp_obj_t *args) {
+    switch (n_args) {
+        case 0:
+            // return a new, empty list
+            return rt_build_list(0, NULL);
+
+        case 1:
+        {
+            // make list from iterable
+            mp_obj_t iterable = rt_getiter(args[0]);
+            mp_obj_t list = rt_build_list(0, NULL);
+            mp_obj_t item;
+            while ((item = rt_iternext(iterable)) != mp_const_stop_iteration) {
+                rt_list_append(list, item);
+            }
+            return list;
+        }
+
+        default:
+            nlr_jump(mp_obj_new_exception_msg_1_arg(MP_QSTR_TypeError, "list takes at most 1 argument, %d given", (void*)(machine_int_t)n_args));
+    }
+}
+
 static mp_obj_t list_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_list_t *o = lhs;
     switch (op) {
@@ -165,6 +188,7 @@
     { &mp_const_type },
     "list",
     list_print, // print
+    list_make_new, // make_new
     NULL, // call_n
     NULL, // unary_op
     list_binary_op, // binary_op
@@ -242,6 +266,7 @@
     { &mp_const_type },
     "list_iterator",
     NULL, // print
+    NULL, // make_new
     NULL, // call_n
     NULL, // unary_op
     NULL, // binary_op