ctypes instances no longer have the internal and undocumented
'_as_parameter_' attribute which was used to adapt them to foreign
function calls; this mechanism is replaced by a function pointer in
the type's stgdict.

In the 'from_param' class methods, try the _as_parameter_ attribute if
other conversions are not possible.

This makes the documented _as_parameter_ mechanism work as intended.

Change the ctypes version number to 1.0.1.