fix (Py_s)size_t as argument type by removing old code that depended on PyArg_ParseTupleAndKeywords()

cleanup unused exception class and some fixes for better runtime behavior in refnanny support module

--HG--
rename : tests/bugs/cdef_bool_T227.pyx => tests/run/cdef_bool_T227.pyx

faster unpacking of optional arguments (10-20%): finding interned strings in a dict is faster than iterating