Fix int/long issue at jnius_proxy.py_invoke0
Fix int/long issue at jnius_proxy.py_invoke0

We need to make a difference between the int and long on Py2 because
of the different storage size which can cause 0L being returned even
if 0 (int) is passed into the function.

    2 ** 31
+-----+-----+
|int  | xxx |
|    long   |
+-----+-----+

kivy/pyjnius,kivy/pyjnius,kivy/pyjnius