Message 131489 - Python tracker

Here is a patch for list.  It modifies the following C API functions:
PyList_SetItem
PyList_Insert
PyList_Append
PyList_SetSlice
PyList_Sort
PyList_Reverse
_PyList_Extend

It also includes tests (with ctypes).

I plan to do next the same for dict, but first I'd wait for comments, to know if I'm doing something completely wrong :-)