Raise Octave errors instead of exceptions for conversion errors * Makefile.am (COMMON_SOURCE_FILES): Include oct-py-error.cc in the list. (PYTAVE_HEADER_FILES): Include oct-py-error.h in the list. * oct-py-error.cc, oct-py-error.h: New files defining error conditions. * oct-py-types.cc (pytave::extract_py_bool, pytave::extract_py_complex, pytave::extract_py_float, pytave::make_py_array, pytave::extract_py_scalar_map, pytave::extract_py_int64, pytave::extract_py_uint64, pytave::extract_py_str): Use new error condition functions instead of throwing exceptions. (pytave::make_py_array, pytave::make_py_numeric_value, pytave::make_py_tuple): Raise Octave error instead of throwing exceptions. * __py_struct_from_dict__.cc (F__py_int64_scalar_value__, F__py_uint64_scalar_value__): Remove exception handling logic. * pycall.cc (Fpycall): Remove conversion exception handlers. * pyeval.cc (Fpyeval): Likewise. * pyexec.cc (Fpyexec): Likewise. * exceptions.h (pytave::pytave_exception, pytave::octave_error_exception, pytave::octave_parse_exception, pytave::value_convert_exception, pytave::object_convert_exception, pytave::variable_name_exception): Delete no longer used exception types.